Page:The Works of William Harvey (part 1 of 2).djvu/315

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ON GENERATION.
215

They who are curious in such matters say that if this cavity be in the point or end of the egg it will produce a male, if towards the side, a female. This much is certain : if the cavity be small it indicates that the egg is fresh-laid ; if large, that it is stale. But we shall have occasion anon to say more on this head.

There is a white and very small circle apparent in the in- vesting membrane of the vitellus, which looks like an inbranded cicatrice, which Fabricius therefore calls cicatricula; but he makes little of this spot, and looks on it rather as an accident or blemish than as any essential part of the egg. The cica- tricula in question is extremely small ; not larger than a tiny lentil, or the pupil of a small bird's eye ; white, flat, and cir- cular. This part is also found in every egg, and even from its commencement in the vitellarium. Fabricius, therefore, is mis- taken when he thinks that this spot is nothing more than the trace or cicatrice of the severed peduncle, by which the egg was in the first instance connected with the ovary. For the pe- duncle, as he himself admits, is hollow, and as it approaches the vitellus expands, so as to surround or embrace, and inclose the yelk in a kind of pouch : it is not connected with the yelk in the same way as the stalks of apples and other fruits are infixed, and so as to leave any cicatrice when the yelk is cast loose. And if you sometimes find two cicatriculse in a large yelk, as Fabricius states, this might, perhaps, lead to the pro- duction of a monster and double foetus, (as shall be afterwards shown), but would be no indication of the preexistence of a double peduncle. He is, however, immensely mistaken when he imagines that the cicatricula serves no purpose ; for it is, in fact, the most important part of the whole egg, and that for whose sake all the others exist; it is that, in a word, from which the chick takes its rise. Parisanus, too, is in error, when he contends that this is the semen of the cock.