ON GENERATION. 247 



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 



