Page:The Works of William Harvey (part 1 of 2).djvu/347

 liquid, the yelk the more earthy and solid one, and, therefore, more apt to sustain the chick when it has once attained to greater consistency and strength ; and further because, as shall be explained below, the yelk supplies the place of milk, and is the last part that is consumed, a residuary portion, even after the chick is born, and when it is following its mother, being still contained in its abdomen.

What has now been stated takes place from the fourth to the tenth day. I have yet to speak of the order and manner in which each of the particulars indicated transpires.

In the inspection made on the fifth day, we observed around the short vein which proceeds from the angle where the two alternately pulsating points are situated, something whiter and thicker, like a cloud, although still transparent, through which the vein just mentioned is seen obscurely, and as it were through a haze. The same thing I have occasionally seen in the more forward eggs in the course of the fourth day. Now this is the ' rudiment of the body, and from hour to hour it goes on in- creasing in compactness and solidity; both surrounding the afore-named vein, and being appended to it in the guise of a kind of globule. This globular rudiment far exceeds the coronal portion, as I shall call it, of the vermicular body ; it is triangular in figure, being obscurely divided into three parts, like so many swelling buds of a tree. One of these is orbicular and larger than either of the other two ; and it is darkened by most deli- cate filaments proceeding from the circumference to the centre ; this appears to be the commencement of the ciliary body, and therefore proclaims that this is the part which is to undergo transformation into the eye. In its middle the minute pupil, shining like a bright point, as already stated, is conspicuous ; and it was from this indication especially that I ventured to conjecture that the whole of the globular mass was the rudiment of the future head, and this black circle one of the eyes, having the other over against it ; for the two are so situated that they can by no means be seen at once and together, one always lying over and concealing the other.

The first rudiment of the future body, which we have stated to sprout around the vein, acquires an oblong and somewhat bent figure, like the keel of a boat. It is of a mucaginous con- sistence, like the white mould that grows upon damp things