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Of Volcher Coiter THE “DE OVORUM GALLINACEORUM GENERATIONIS PRIMO EXORDIO PROGRESSUQUE, ET PULLI GALLINACEI CREATIONS ORDINE” OF VOLCHER COITER TRANSLATED AND EDITED WITH NOTES AND INTRODUCTION BY HOWARD B. ADELMANN, PH.D. ITHACA, N. Y. Part ii. Conclusion* As for myself, in May 1564 at In the middle I saw something resem­ Bologna, stimulated by Doctor bling semen.25 The point and the circle Ulysses Aldrovandus (that most were found under the membrane sur­ distinguished professor of ordi­ rounding the substance of the egg. They nary philosophy, a man expert in the were bestrewn with certain sanguineous knowledge of the various sciences and filaments. The white, like the yolk, was a arts as well as of philosophy and especi­ little more fluid than usual. The white ally natural philosophy, my encourager glass-like substance,26 which is com­ and teacher to be cherished with per­ monly held to be the semen of the cock, petual regard), and encouraged by other was a little harder. teachers and students, I had selected No change in the albumen was detected two clucking hens ready for incubation. on the third day;27 but the sanguineous Under each of them I had placed twenty- point or globule previously found in the three eggs17 and in the presence of those yolk, but now found rather in the albu­ men, I opened one on each day, in order men,28 manifestly pulsated29 and, as we that we might determine these two things were able to judge by the color, gave rise especially, to wit—the origin of the veins to one venous trunk which, after dividing and what is first formed in the animal.18 into two,30 gave off many small branches In an egg of the first day19 I saw that which encircled the pulsating point. These the yolk had acquired a white circle which small branches were supported by a very was not very large. In its middle there thin membrane which represented the was a point or disc of the same color. secundine31 both in function and sub­ From the circle two similar circles20 stance. Hence three membranes were flowed away. One of them was thicker and found here; the first32 is assigned to the longer than the other. The yolk was more shell, the second33 to the whole substance fluid than the yolk of a fresh egg. of the egg and the third to the secundine.31 On the second day21 I saw two very On the fourth day I opened the egg thin pellicles or membranes, one of which from the blunter end and there occurred adhered immediately to the shell;22 the first a space so empty that it easily other, which surrounded the substance admitted the first joint of the finger. of the egg, was separated a little from the The aqueous white, on account of its shell,23 for a small space at the end of the tenuity, flowed off. The globule and the egg was empty. The yolk had risen other structures were found to be larger. toward the pointed end of the egg as Moreover, the globule pulsated; the Aristotle24 says happens on the third vessels did not. On one side,34 three day. The middle part of the yolk was translucid, glass-like globules were found seen to be clearer than the remaining joined to one another. On the other side portion. there were two branches or vessels,35 * Part i appeared in the July issue of the Annals of Medical History, n.s. 5:327, 1933. not unlike arteries; which, however, did There was nothing more perfect or larger not pulsate. When the albumen had been than the eyes. For, although I had some poured off, the rather liquid yolk came difficulty, I was able to distinguish from into view. It was besprinkled here and one another all the tunics and humors in there indiscriminately with blood. the eyes. Hence from the fact that in On the fifth day we observed that the birds the eyes are developed first, Lac- second membrane, surrounding the whole tantius Firmianus43 decided, not without substance of the egg and perfused with reason, that the head begins to develop many veins,36 was so free from the shell­ first in birds. Perhaps the eyes, just as membrane and so strong that, without very ingenious and elaborate instruments, injury, it could be removed together require a long time for completion. with the substance of the egg. When Wherefore, since birds remain in the this membrane was opened, I saw that egg for a short time, the creator of things the sanguineous, pulsating globule had commences to weave this fabric first with sunk more deeply than usual. I took an the eyes. Furthermore, superiorly between egg of the fifth day from each hen. There the eyes there was a rather large, trans­ appeared in one of them merely the still parent globule which has been seen to formless pulsating globule which was, represent the brain. Below the eyes there however, surrounded by blood vessels, was something resembling a beak. as has been stated. The lateral globules37 On the seventh day everything could tended to be black in color. Between be seen more clearly; first, the three them there were still smaller connected pellicles, especially the third called the globules,38 which represented the brain secundine44 which supports the veins and after a fashion. The third globule39 was surrounds all the fluid. When the yellow­ unchanged except in size. In the albumen ish white fluid had been poured off, the dissimilar parts were seen. Some were small, rudely-formed animal appeared. thin and approached glossy whiteness, Its head was larger and more perfect others were denser. The yolk was easily than the other parts of the body. Both mixed with the albumen. In the other egg the cranium and the beak were observed the head of the chick clearly appeared to be more perfect. The rest of the body very large with respect to the size of the and its members were formless. I was body. On both sides of it there was a able to distinguish almost none of the blackish eye, which was found to be very viscera both because they were included clear in the middle. Between the eyes in the thorax and because internally there was a third globule.40 The rest of they had not yet attained their true the rather long body hung down from and manifest form, for they were seen the head. The heart or pulsating disc was to be in disorder everywhere. situated not far from the head. From it On the eighth day I found that all the veins were seen to arise. I was able parts including the legs and wings were to find no trace of the liver, so confused larger and better formed, so that the were the viscera. embryo already exhibited the likeness On the sixth day, in addition to the of a chick. It moved around in the other parts which were all larger, we albumen45 with more vigorous motion. saw from the blunter end, after the In addition I found rather conspicuous . 41 of the membranes or pellicles, veins46 entering the umbilicus of the the albumen first, for the yolk remained chick. in the bottom of the egg. The living, On the ninth day I observed that the animate chick, imperfectly delineated in secundine4' had increased with respect all its parts, floated in the albumen.42 to the number and size of its veins. It had been granted a head which was In short, it was more distended with blood very large in proportion to the body. than usual; some very thin blood had even transuded. After the secundine, and was white in color like the spermatic the chick was visible floating in the parts.56 The lung and the ribs were white with half of the yolk on each side formed. In the lower part of the belly as if the yolk had been cut into two equal were the liver which tended from white parts.48 The umbilical vessels were much to reddish in color, the stomach and the larger. After the chick had been taken intestines which were very white. Two out, I removed the proper membrane49 umbilical vessels57 emerged from the immediately surrounding the chick so belly of the fetus next the anus and that it might not perish in the liquid. proceeded to the yolk. When the chick The chick was now perfect in all parts had been removed, we noticed that and it was observed to have large pores the greater part of the albumen had been everywhere, from which the primordia used up and what remained was a dense of feathers were about to emerge. The excrement. Little of the yolk, however, head was largest of all. The eyes were had disappeared. very perfect indeed and provided with On the eleventh day we found no lids. I saw three transparent globules difference except in size. The head had in the head, the combination producing grown more evident and the feathers the form of the avian brain. All parts had sprouted a little. The fetus, resting below the neck had attained their com­ upon the yolk, floated in a white and plete and natural form. A pulsation tenuous albumen.58 The dense and viscid appeared externally in the thorax in albumen adhered below the yolk. the region of the heart. The heart had On the twelfth day, in addition to attained its form and was whitish in other things we examined the membranes color.
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