[257] EXERCITATIO DECIMAOCTAVA.
Quarta ovi inspectio.

18th exercise
The fourth inspection of the egg

QUINTO demum ab incubatione die, discernitur primum, inquit Aristoteles[1], corpus pulli valde exiguum, et candidum; capite conspicuo, et in eo oculis maxime turgidis, qui diu sic permanent. Sero enim tandem parvi fiunt, ac considunt. In parte autem corporis inferiore nullum extat membrum per initia, quod respondeat superioribus. Meatus autem illi qui a corde prodeunt, alter ad circundantem membranam tendit, alter ad luteum, officio umbilici. Pulli igitur origo ex albumine est; alitur enim luteo per umbilicum.

Finally the fifth day from the beginning of incubation Aristotle* says: «First of all a body of the chick is seen that is very small and white, with a big head, and in this are present very swollen eyes remaining for a long time this way. Finally in fact beyond they become small and decrease. But in the inferior part of the body any sketchy structure corresponding to the superior ones doesn't exist. Of those vessels sprouting from the heart, one goes to the winding membrane, the other to the yolk with the function of navel. Therefore the origin of the chick comes from the albumen, in fact it is fed by the yolk through the navel.»

Quibus verbis, Aristoteles videtur totam pulli generationem in tres classes sive ordines distribuere: nempe a primo incubationis die ad quintum usque; inde ad diem decimum vel decimum quartum; atque hinc ad vicesimum. Quasi ea duntaxat, quae his tribus temporibus percepit, in historiam retulisset. [258] Contingunt sane his temporibus maximae in ovo permutationes: quasi diebus hisce decretoriis ceu tribus gradibus, processus ab ovo perfecto ad pulli exclusionem distingueretur. Quarto enim die prima foetus particula, punctum saliens nempe, et sanguis apparent; posteaque foetus corporatur. Septimo, pullus membris distinguitur, et sese movet. Decimo, plumescit. Circa vicesimum, respirat, pipit, atque exitum quaerit. Vita, quae illi ante quartum diem inest, plantarum aemula videtur, atque anima vegetativa duntaxat censenda est. Inde vero ad decimum, animalis instar, sensitiva atque motiva anima fruitur, qua adolescit: posteaque sensim perficitur; ornatus plumis; et rostro, unguibus, reliquisque instructus, ad exitum iam properat, ut tandem emancipatus sui iuris fiat.

It seems that Aristotle with these words divides the whole generation of the chick in three classes or orders: that is, from the first day of incubation until the fifth, hence until the tenth or the fourteenth day, and hence until the twentieth. As if he recorded in the description only those things he observed in these three intervals of time. Actually in these intervals of time very big changes happen in the egg, as if the passage from the completed egg to the hatching of the chick is identified by these decisive days as being three stages. In fact on the fourth day are appearing the first particle of the fetus, that is, the pulsating point, as well as the blood, and subsequently the fetus takes a body. At the seventh day the chick is marked by the limbs and stirs. At the tenth day it grows feathers. About the twentieth day it breathes, peeps and tries to go out. The life present in it before the fourth day seems to emulate the plants, and we have to record only the vegetative soul. But since then until the tenth day, as an animal, it has a sensorial and motor soul, thanks to which it increases and subsequently slowly becomes perfect. Adorned with feathers and endowed with beak, toenails and remaining structures, it already hastens to go out so that, finally emancipated, becomes independent.

Quae itaque post quartum diem eveniunt, Aristoteles tria potissimum enumerat: nempe corporis fabricam; venarum ductus, qui iam umbilici officium et naturam subeunt; materiamque, unde foetus primum oritur, constituitur, et nutritur.

Therefore, among the things happening after the fourth day, Aristotle lists above all three of them, that is: the structure of the body, the venous ducts already carrying out the task and the shape of the navel, and the matter from which the fetus originates, is formed and fed.

De corporis fabrica, quatuor recenset: scilicet, quae sit eius magnitudo; quis color; quae partes maxime conspicuae sint (caput nimirum, et oculi) et quaenam sit membrorum distinctio.

About the structure of the body he examines four things, that is: what is its size, what the colour, what are the larger parts (that is, head and eyes), and what is the subdivision of the parts of the body.

Est revera corpus valde exiguum, formaque galbam vulgarem referens, ex qua musca oritur; colore etiam candido praeditum est; perinde ac muscae vermiculus, quem in carne putrescente foventem atque enutriendum deponit. Eleganter etiam addidit, conspicuum maxime esse capite et oculis. Quod enim primo apparet, similare est et indistinctum; tanquam concretum et congelatum quid ipsius colliquamenti foret (qualis gelatina apparet, quae ex cornu cervini coctura efficitur); nempe transparens nubecula, et vix conspicua, nisi in duas quasi partes divisa distingueretur. Quarum altera conglobata, longe altera maior est; capitis scilicet rudimentum, quod die quinto [259] primum conspicitur: in eoque mox oculi manifeste distinguuntur; qui per initia statim maximi, valdeque inflati prominent, et a reliquo capite atque etiam corpore, circumfusa quadam nigredine, discriminantur. Horum quilibet reliquo toto capite maior est; quemadmodum et caput ipsum, corpus reliquum magnitudine excedit. Durat aliquandiu hic corporis candor, et oculorum intumescentia (qui, perinde ac cerebrum, aqua intus limpidissima implentur, foris autem nigricant); ad decimum nempe diem atque etiam amplius: sero enim, inquit, decrescunt oculi, et sese ad ratam contrahunt proportionem. Imo vero, me observatore, oculi avium nunquam sese ad ratam illam proportionem contrahunt, quae est inter oculum et caput animalis vivipari. Gallinae enim, aliisque avibus, si cutem oculos integentem detraxeris, horum quilibet totam cerebri molem facile aequaverit: in beccagine autem et similibus, alteruter oculus toto reliquo capite, si rostrum dempseris, maior est. Omnibus vero avibus id commune est, ut orbita sive cavitas, quae oculum amplectitur, cerebrum ipsum exsuperet, ut in ipsarum craniis videre est. Fit autem ut earum oculus minor videatur, quia totus praeter pupillam cute et plumis obtegitur; neque orbiculari figura praeditus est, qua promineat, sed depressiore; ut piscibus contingit.

In truth the body is very small and in shape it resembles to the common worm of the oak from which a fly is born, and it is also endowed with white colour as the small worm of the fly which lays it in decaying flesh to heat and feed it. In an elegant way he also added that it is very big at head and eyes level. In fact what appears at the beginning is quite similar and indistinct, as if something of the colliquation itself was thick and frozen (as the jelly from a cooked horn of deer is appearing), just a small transparent patch, and hardly visible if didn't appear divided into almost two parts. One of the two parts is rounded and the other is much greater, that is, is the sketch of the head that becomes visible for the first time on the fifth day, and at once the eyes are clearly recognizable in it, which in the initial phases immediately stick out very big and very swollen, and they are recognisable from the rest of the head as well as of the body because of some blackness placed around. Each eye is greater than the whole remaining head, so as the head itself overcomes in size the rest of the body. This snowy whiteness of the body lasts for a certain time, as also the swelling of the eyes (which, as the brain, are internally filled by very clear water, while on the outside they are black) until toward the tenth day and also more; in fact he says that belatedly the eyes decrease and contract to the correct proportion. But rather, according to my observation, the eyes of the birds never contract to that right ratio existing between the eye and the head of a viviparous animal. In fact if from a hen and other birds you will remove the skin covering the eyes, any one of them easily will equalize the whole mass of the brain; besides in the woodcock* and in similar birds each eye is larger than the whole remaining head, but having removed the beak. In truth all the birds have in common what follows: the orbit, that is, the cavity embracing the eye, exceeds the brain itself, as it is possible to see in their skulls. But it happens that their eye seems smaller since it is fully covered by skin and feathers except the pupil, and it is not endowed with spherical shape through which to stick out, but more flattened, as it happens in fishes.

In parte corporis inferiore, inquit Philosophus, nullum exstat membrum per initia quod respondeat superioribus. Ita profecto se res habet: corpus ab initio, ut, vix nisi capite et oculis, conspicuum est; ita quoad inferiora, nec membro aliquo, alis scilicet, pedibus, sterno, uropygio, nec viscere ullo distinguitur; imo vero neque formam quidem corporis ullam obtinet: sed, quantum nobis videre licuit, est exiguum quid venulae adiacens, tanquam carina naviculae circumflexa, et quasi galba, vel termes, absque ullo costarum, pedum, alarumve vestigio; cui corpusculum conglobatum, multoque conspectius appenditur, scilicet [260] capitis rudimentum, in tres veluti bullas divisum, ab alterutra scilicet parte intuenti: revera tamen in quatuor dispescitur; quarum duae amplissimae et nigricantes, oculorum primordia sunt; reliquarum altera cerebrum, altera cerebellum constituit. Omnes aqua limpidissima plenae reperiuntur: in medio vero oculorum nigredinis, tanquam in centro, pupilla cernitur, instar scintillae transparentis, aut crystalli, effulgens. Hinc factum arbitror, ut tres solum conspicuae bullae, male rem observantibus imposuerint. Cum enim ex veteri scholarum disciplina, triplicem in corpore animalis dominatum didicissent, partesque tres principales, cerebrum nempe, cor, et iecur, praecipuis muneribus fungi crederent; facile, tres dictas bullas, partium harum fundamenta atque initia esse, sibi persuaserunt. Coiterus autem, ut peritum dissectorem decuit, multo verius affirmat se, die ab incubatione septimo, rostrum atque oculos vidisse; nullum vero ex visceribus potuisse discernere.

The Philosopher says: «In the inferior part of the body doesn't exist any sketch of structures corresponding to the upper ones.» Really the situation is this: as the body from the beginning is big only because of head and eyes, as much, as far as the inferior parts is concerning, it is not distinguishable for any limb or body part, that is, wings, feet, sternum, uropygial gland, neither for any entrails. Or rather, in truth, it doesn't possess any shape of a body, but, as far as it has been possible for me to see, there is something small near the little vein, similar to the circumflex keel of a small ship, and almost as a worm or a twig, and without any sketch of coasts, feet or wings, to which a rounded and very more visible corpuscle is suspended, that is, the sketch of the head divided as into three bubbles, obviously for him who is looking from only one side. Really however it is divided into four bubbles, two of them very wide and blackish being the sketches of the eyes; one of remaining bubbles is the brain, the other is the cerebellum. All of them are found full of very clear water. But in the middle of the black of the eyes, that is, in the centre, the pupil is seen shining as a transparent spark or a crystal. From this I think is coming the fact that to those people who made a superficial observation only three bubbles highlighted. In fact having learned from the ancient scholastic teachings that in the body of the animal a triplex dominion exists, and since they believed that the three principal parts, that is, brain, heart and liver performed special functions, easily they became convinced that the three above-mentioned bubbles are the bases and the beginnings of these parts. But Volcher Coiter, as it is suitable for an experienced dissector, in a way very more corresponding to the truth he affirms that starting from the seventh day of incubation he has seen the beak and the eyes, but that he has not been able to locate any entrails.

Philosophum porro audiamus: Meatus illi, qui a corde prodeunt, alter ad ambientem membranam tendit, alter ad luteum, officio umbilici. Nimirum corporato statim foetu, venae istae umbilici officium praestant: earumque alterius rami seu propagines in tunicam extimam albumen ambientem disseminantur; alterius vero rami, vitelli tunicam adeunt, et per huius liquorem sparguntur. Unde clare constat, utrumque pariter liquorem nutriendo pullo dicatum esse. Et licet Aristoteles dicat, originem pulli ex albumine esse, atque ali luteo per umbilicum: non ait tamen, pullum ex albumine fieri. Quippe ex candido illo liquore, quem nos colliquamentum nominavimus, fit foetus: et totum illud, quod nos oculum ovi nuncupavimus, in albumine continetur. Neque ait, victum pullo solum ex luteo per umbilicum accedere: sed verba eius, ex observationibus meis, hoc sensu interpretor; licet pullus in albumine originem suam habeat, non tamen inde solum alitur, sed etiam ex luteo, [261] ad quem meatuum umbilicalium alter pertingit, sibi victum quaerit; imo vero ex hoc potissimum; est enim albumen, ex sententia Aristotelis, concoctus magis et purior ovi liquor; vitellus autem terrestrior et solidior, ideoque robustiori iam facto pullo nutriendo idoneus: ac propterea, ut infra dicetur, vicem lactis supplet, ultimoque absumitur; quippe pars eius residua, postquam iam natus est pullus, et cum matre obambulat, in ventre ipsius continetur.

We listen also the Philosopher: «Those ducts coming from the heart, one goes toward the winding membrane, the other toward the yolk with the function of navel.» Really, as soon as the body of the fetus is outlined, these veins carry out the task of navel, and the branches or offshoots of one of the two veins scatter the surrounding albumen in the more external tunic, while the branches of the other vein go towards the tunic of the yolk and are disseminated through its liquid. Hence it clearly results that both the liquids are likewise devoted to feed the chick. And it is permissible that Aristotle says: «The origin of the chick comes from the albumen and it is fed by the yellow through the navel.» Nevertheless he doesn't say that the chick is generated from the albumen. In fact the fetus is generated from that white liquid I called colliquation, and all what I called eye of the egg is contained in the albumen. Neither he says that the nourishment comes to the chick only from the yolk through the navel, but I interprets in this meaning his words according to my observations, that is, that the chick has its origin in the albumen, but that nevertheless it is not fed only by it, but it asks food for itself also from the yolk, to which the other of the umbilical vessels comes, or rather, above all from this. In fact according to the affirmation of Aristotle the albumen is the liquid of the egg more digested and purer, while the yolk is more earthly and denser, and therefore suitable for feeding the chick when already more strengthened. And therefore, as I will say later, it stands in for milk and is consumed as last, since its residual part, when the chick already hatched, and when walks with the mother, is contained in its abdomen.

Quae dixi, a quarto die ad decimum usque eveniunt. Quando autem singula, quomodo, et quo ordine fiant, iam expediam.

The things I have said happen from the forth until the tenth day. But now I will expose when, how and in what order the single things happen.

Proxima inspectione, quae die quinto instituitur, circa venam brevem ab angulo ductam, ubi duo puncta alternatim micantia sita sunt, crassius aliquid et albidius, nubeculae instar (transparens tamen) apparet: per quod praedicta vena obscure, ceu per nebulam, conspicitur. Idem aliquando, in ovis provectioribus, quarto die sum conspicatus. Est autem corporis rudimentum; quod iam singulis horis concretum magis compactumque cernitur; venamque praedictam et amplectitur simul, et illi, globuli alicuius instar, appenditur. Rudimentum id globosum, vermiculi huius, ut sic dicam, carinam magnitudine longe superat: estque figurae triquetrae, in tres nempe partes (protuberantis arboris gemmulae more) obscure divisum. Earum una orbicularis est, et reliquis duabus maior; ductisque mox a circumferentia versus centrum tenuissimis filamentis, nigricat; septique ciliaris exordium apparet, indeque particulam hanc in oculum mutatum iri indicat. In huius medio, pupilla admodum exigua, et puncti lucidissimi instar, ut diximus, conspicua est: eoque potissimum indicio coniecturam feci, integrum hunc globulum futuri capitis rudimentum esse; circulumque illum nigrum, ex oculis alterum futurum, cui ex adversa parte alter opponitur: quippe ita siti sunt, ut ambos simul intueri nequeas, cum superior inferiorem obtegat et occultet.

With the next inspection, which is undertaken at the fifth day, around the brief vein coming from the angle where the two alternatively pulsating points are situated, something denser and more white is visible, as a little cloud (however transparent), through which the aforesaid vein is confusedly perceived, that is, through a little cloud. Sometimes I have seen the same thing on the fourth day in more advanced eggs. Actually it is a sketch of the body which already with the passing of the hours appears more thick and compact, and contemporarily embraces the above-mentioned vein and hangs itself to it as being a small globe. Such globular sketch in greatness overcomes by far the keel of this, so to say, small worm, and it is of triangular shape, that is, coarsely divided into three parts (as the small gems of a sprouting tree). One of them is circular and greater than the remaining two, and after having immediately sent forth very thin filaments from the circumference toward the centre, it becomes black, and the beginning of the palpebral septum appears, and then it points out that this particle turns into an eye. At its centre the very small pupil is visible and, as I said, similar to a very bright point. Above all according to such sign I hypothesized that this whole globule is the sketch of the future head, and that from the eyes that other black circle will be born, to which another eye is opposed at the opposite side, since they are located in such a way that you don't succeed in seeing both at the same time, since the superior one covers the inferior and hides it.

[262] Primum hoc futuri corporis rudimentum, quod circa venam concrescere diximus, figuram solum oblongam, et aliquantulum, carinae instar, inflexam obtinet: estque consistentia eius mucosa, instar situs candidi, qui rebus humidis arcteque conclusis innasci solet. Venula autem, cui mucorem illum accrescere iam dixi, est cava descendens per spinam dorsi; uti subsecutae observationes fidem fecerunt. Duarum quoque vesicularum pulsantium ordinem si diligenter intuitus fueris, quae posterius se contrahit, eam sanguinem in huius venae principium impellere, eamque distendere conspicies.

This first sketch of the future body, that we said is developing around the vein, has only a lengthened and a little bit bent aspect as a keel, and its consistence is mucous as the white area which is accustomed to be born in the damp things and contained in a narrow space. But that little vein, close to which I already said that that mucilaginous substance grows, is the vena cava and goes down along the backbone, as next observations confirmed. If with diligence you will observe also the arrangement of the two pulsating vesicles, you will see that, that one is contracting, later pushes the blood in the initial part of this vein and spreads it.

Ita duarum vesicularum sese moventium atque invicem pulsantium, duae manifestae contractiones, duaeque similiter dilatationes cernuntur; priorque unius contractio alterius distensionem efficit: sanguis enim, ex cavitate prioris vesiculae coarctata elisus in secundam, hanc implet, distendit, pulsumque edit: quae mox etiam se constringens, sanguinem, quem iam a priore vesicula acceperat, in praedictae venae principium protrudit, eamque simul dilatat. Venam autem adhuc appello, quam ex pulsu aortam esse censeo: arteriae enim a venis, tunicarum crassitie, nondum distinguuntur.

Thus two evident contractions are seen and alike two dilations of two vesicles alternatively moving and pulsating, and the previous contraction of the one induces the dilation of the other. In fact the blood, expelled in the second vesicle from the cavity of the previous vesicle which contracted, fills the second, spreads it and produces a pulsation, and it also, at once contracting, ejects in the initial part of the above-mentioned vein the just received blood from the previous vesicle and simultaneously dilates it. Actually I still call vein that which according the pulsation I think to be the aorta: in fact the arteries don't differ from the veins for the thickness of the walls.

Haec cum saepius in plurimis ovis diligenter accurateque contemplatus essem, aliquandiu pendebam animi, quamnam sententiam amplecterer. Utrum scilicet concrementum hoc, globulusque appensus, ex colliquamento, in quo natabant, tanquam ex materia compacta et coagulata, proveniant; quemadmodum ex vaporibus (dum sursum meant, imperceptibilibus) in aere superiore condensatis nubes fiunt: an potius ab effluvio quodam e sanguineo isto meatu exhalante, vel per diapedesin transudante, exoriantur; mutuatoque inde nutrimento augeantur? Sunt enim maximarum quoque rerum initia perpusilla et, prae exiguitate sui, obscura admodum.

Having rather often observed with diligence and accuracy these things in a lot of eggs, for some time I was hesitant on what thesis to embrace. That is, if this condensation and the suspended globule come from the colliquation in which they floated, as from a compact and coagulated matter, like from the vapours (imperceptible when they go upward) condensed in the high air the clouds are formed, or if rather they are born from a certain outflow coming out from this venous blood vessel or oozing for diapedesis, and which grows for the nourishment hence it took? In fact also the beginnings of the very big things are extremely small and, for their small dimensions, very vague.

[263] Hoc sane exploratum me habere arbitror, puncta salientia, et meatus venales, ipsamque venam cavam primum existere, eique postea corpulentiam dictam accrescere. Certusque sum, sanguinem e puncto saliente in venam hanc impelli; ex eaque corpusculum illud nutriri et crescere. Nempe primus ille situs et mucor, ex effluvio venae, cui adnascitur, primum oritur; indeque postea nutritur, atque augetur; quemadmodum situs alibi solet, in locis humidis, inter opaca domus, quae diu non repurgatur; et ut camphora super tabulas cedri; et muscus super saxa, et arborum cortices; aut denique, qualiter erucis quibusdam tenuis lanugo innascitur.

I think to have truly explored what follows: the pulsating points and the venous vessels, and that at first the vena cava itself exists and that subsequently the so-called corpulence is added to it. And I am sure that the blood is pushed by the pulsating point in this vein and that by it that corpuscle is fed and grows. Just that first point and the mucilaginous substance at first are born from the outflow of the vein near which they are formed, and subsequently they are fed by it and increased, alike elsewhere a point is accustomed to do, in damp places inside tenebrous places of a house that for a long time is not cleaned, and as the camphor above the tables of cedar, and the musk above the stones and the barks of the trees, or, finally, like on some caterpillars a thin fluff is born.

Eadem quoque occasione dubitabam, numnam, facta colliquamenti coagulatione, una cum sanguine et puncto saliente, hoc etiam corporis capitisque rudimentum statim exsisteret; sed tenue adeo et pellucidum, ut visum prorsus effugeret; donec in situm ac mucorem crassescens, albedinem spissiorem induat, qua percipiatur: dum interea sanguis crassior et rutilans in colliquamento tam diaphano facile conspicitur. Verumenimvero, cum pressius rem ipsam cogito, in ea sententia sum; sanguinem dari, antequam quidquam corporis reliqui exsistat; esseque eum, prae caeteris omnibus foetus partibus, primogenitum: et ab ipso, tum materiam, ex qua corporatur foetus, tum nutrimentum, quo augetur, procedere: esse denique (si modo ulla fuerit) primam particulam genitalem. Id autem ut credam, quibus argumentis adducar, postea fusius dicetur; ubi de parte genitali prima, de calido innato, et humido radicali disceptabimus; et simul etiam, quid de anima sentiendum sit, pluribus collatis observationibus, determinabimus.

In the same moment I also doubted if, when the coagulation of the colliquation together with the blood and the pulsating point happened, also this sketch of body and head certainly existed, but thin and transparent to such a point to escape entirely the sight, until when by thickening in the point and in the mucilaginous substance it wears a denser whiteness through which it is identified, while in the meantime the thicker and red blood is easily seen in such a transparent colliquation. Truly in fact when I think about this thing with greater caution, I conclude that the blood is supplied before anything of the remaining body exists, and that it, in comparison to all the other parts of the fetus, is the first-born. And that from it are coming both the matter from which the fetus takes shape, and the nourishment by which it is increased. In short, it is the first genital particle (if just someone there has been). Subsequently I will say rather widely by what reasoning I am induced to believe this, when I will discourse on the first genital part, on the innate heat and on the radical dampness, and at the same time we will also establish what we have to think about the soul after having gathered many observations.

Circa hoc tempus, singulis pene horis omnia maiora, manifestiora, magisque distincta et explicata apparent; fitque in ovo velox mutatio, plurimaque confestim alia aliis superveniunt. Cavitas ovi iam multo auctior, totamque eius partem superiorem [264] vacuam relinquit; tanquam quinta pars ovi absumpta foret.

In this period of time almost every hour all the things appear greater, more manifest and more distinct and evident, and in the egg a quick change happens, and quickly a lot of other things are added to the others. The cavity of the egg is already more greater and leaves empty its superior part, as if a fifth part of the egg had been consumed.

Venarum ramuli longius protelantur, pluresque numero non solum in colliquamentum, ut antea, sed hinc in albumina, illinc in luteum distribuuntur; amboque adeo liquores passim fibris sanguineis scatent. Vitelli pars superior plurimum colliquescit et funditur, ut ab inferiore plane diversa appareat, iamque duo quasi vitelli videantur; dum superior, cerae liquefactae instar, ut diximus, inflatus et pellucidus emicat; inferior autem et densior, una cum albuminis parte crassiore, ad acutum ovi angulum subsidit. Estque adeo tenuis vitelli superioris tunica propria, ut a minima concussione facile rumpatur: unde liquorum commixtio, ut diximus, et generationis frustratio.

The twigs of the veins go away even more, and in very high number they are distributed not only in the colliquation, as previously, but partly in the albumens, partly in the yolk, to such a point that both liquids abound anywhere of blood filaments. The superior part of the yolk liquefies quite a lot and melts, so to appear quite different from the inferior one, and by now they seem to be almost two yolks, while the superior one, as liquefied wax, as I said, is resplendent bulgy and bright, while the inferior and denser moves toward the acute angle of the egg together with the thicker part of the albumen. The proper tunic of the superior yolk is thin to such a point to easily break at the slightest shock, whence are coming, as I said, the mixture of the liquids and the failure of the generation.

Iam primum foetus rudimentum sese conspiciendum exhibet, quemadmodum in Fabricii figura quinta et sexta videre est, eoque in aquam limpidam immisso, quid corporis factum sit, quid etiamnum desideretur, cognitu facile fuerit. Apparet nempe forma vermiculi sive galbae; sicut in frondibus arborum, corticum pustulis, fructibus, floribus, alibique vermium et erucarum primordia conspicimus; praesertim vero in gallis quercinis, quarum in centro, intra crustulam rotundam, ceu nucleum, liquor limpidus continetur, qui sensim crassescens et coagulatus, subtilissimis lineamentis distinguitur, galbaeque formam induit: manet autem aliquantisper immobilis, posteaque motu et sensu praeditus, fit animal, tandemque musca avolat.

Now the first sketch of the fetus shows itself to the sight, as it is possible to see in the fifth and in the sixth figure of Fabrizi, and after we put it in clear water it will be easy to know what part of the body is structured and the lack of what part is still present. Really it shows itself with the shape of a small worm or a worm of the oak, as in the leafy branches of the trees, in the vesicles of the barks, in the fruits, in the flowers and elsewhere we see the sketches of the worms and of the caterpillars, especially in the galls of the oak*, in whose centre, inside a round little crust, or nucleus, a clear liquid is contained, which slowly thickening and after coagulated is divided by very narrow lines and takes the shape of a worm of the oak: but for some times it remains immobile, and afterwards, endowed with movement and sensibility, becomes an animal and at the end a fly flies away.

Similem generationem eorum, quae sponte nascuntur, Aristoteles[2] descripsit: Quaedam e rore gignuntur, qui super folia deciderit. Pauloque post, Fiunt papiliones ex erucis. Haec autem ex foliis virentibus; potissimum raphani illius, quam brassicam vocant aliqui. Primum milio minor est, deinde minuti [265] vermes: tum crescentes intra triduum erucae pusillae: posthaec auctae a motu cessant, et formam mutant, vocanturque chrysalides, crustaque dura continentur; atque, si attingantur, motum edunt. Crusta multo post tempore abrumpitur tandem, unde alata animalia evolant, quos nominant papiliones.

Aristotle described a similar generation of those animals that are spontaneously born: «Some are born from the dew settled on the leaves.» And a little more ahead: «Butterflies are formed from the caterpillars. The caterpillars are formed from the green leaves, above all of that radish called cabbage by some people. At first it is smaller than a grain of millet, then they are small worms, then, growing, in the turn of three days they become small caterpillars; subsequently, being increased, they stop stirring and change aspect and are called chrysalises and are contained in a hard involucre, and if touched they move. The involucre finally breaks after a lot of time and from it some winged animals called butterflies fly away.»

Nos vero quorumlibet animalium generationem eodem modo fieri infra docebimus; omnia nimirum animalia, etiam perfecta, similiter ex vermiculo gigni.

Later I will explain that the generation of whatever animal happens in the same way, that is, all the animals, also perfect, are produced in a similar way from a little worm.

Quod etiam Aristoteles videtur annuisse, ubi ait[3]: In omnibus autem vel iis quae perfectum pariunt ovum, conceptus primus indiscretus adhuc recipit incrementum: qualis natura etiam vermis est. Hoc nempe inter vermis, aliorumque animalium generationem interest; quod ille prius augeatur, quam figuretur, aut in partes distinguatur; secundum illud Philosophi[4]: E verme ita fit animal, ut non ex eius parte, sicut ex ovo, sed totus crescat et dearticulatum animal evadat: scilicet, augmento discretus.

Also Aristotle seems to have mentioned this when he says: «But in all or in those laying a perfect egg, the indistinct initial conception takes further increase, as also the nature of the worm is.» This is just in the middle between the generation of the worm and of the other animals, since it increases before taking an aspect or dividing into parts according to that affirmation of the Philosopher: «From a worm an animal is formed in such way that it grows not from one of its part as from an egg, but complete, and an articulated animal comes out», that is, divided by the growth.

Est equidem quod miremur, animalium omnium, praesertim sanguineorum (puta canis, equi, cervi, bovis, gallinae, serpentis, hominis denique ipsius) primordia, tam plane galbae figuram et consistentiam referre, ut oculis internoscere nequeas.

Certainly we remain surprised that the sketches of all the animals, above all of those endowed with blood (as of dog, horse, deer, ox, hen, snake, and finally of the man himself) so much clearly show an aspect and a consistence of the worm of the oak that you would not be able to distinguish them with the eyes.

Sub finem quinti diei, vel initio sexti, caput in tres vesiculas distinguitur: quarum prima, maxima, rotunda, et nigricans, est oculi; in cuius centro pupilla, veluti punctum crystallinum, conspicitur. Sub hac minor vesicula, quae cerebrum refert, ex parte delitescens cernitur: cui tertia, tanquam apposita crista, sive apex rotundus, supereminet; ex qua tandem cerebellum effingitur. In omnibus vero, praeter aquam limpidissimam, nihil reperias.

Toward the end of the fifth day or at the beginning of the sixth, the head is divided into three vesicles, the first, very big, round and blackish, belongs to the eye, at whose centre the pupil is seen as if being a crystalline point. Under this a smaller vesicle is seen, similar to the brain, which partially is hidden, to which a third one overlaps as being a tuft set nearby or a round apex, from which the cerebellum is finally shaped. In all you won't find anything else than very clear water.

Iam rudimentum corporis, carinam diximus, spinam dorsi luculentius refert; cui latera exstructa assurgere incipiunt: alae [266] nimirum et pedes e galba aliquantulum protuberant. Venarum meatus nunc plane umbilicum referunt.

The sketch of the body I called keel, resembles much more the spine, whose sides start to become more high, and just the wings and the feet stick out a little bit from the worm of the oak. Now the venous ducts entirely resemble a navel.