ANIMALS. 379 



without form, showing, at the end of seven days, 

 pretty much such an appearance as that of the 

 chicken after four-and-twenty hours, being a 

 small jelly-like mass, yet exhibiting the rudi- 

 ments of the head ; the trunk is barely visible ; 

 there likewise is to be discerned a small assem- 

 blage of fibres issuing from the body of the in- 

 fant, which afterwards become the blood-vessels 

 that convey nourishment from the placenta to 

 the child, while enclosed in the womb. 



Fifteen days after conception the head becomes 

 distinctly visible, and even the most prominent 

 features of the visage begin to appear. The nose 

 is a little elevated ; there are two black specks in 

 the place of eyes ; and two little holes, where 

 the ears are afterwards seen. The body of the 

 embryo also is grown larger ; and both above 

 and below, are seen two little protuberances, 

 which mark the places from whence the arms 

 and thighs are to proceed. The length of the 

 whole body at this time is less than half an inch. 



At the end of three weeks, the body has re- 

 ceived very little increase ; but the legs and feet, 

 with the hands and arms, are become apparent. 

 The growth of the arms is more speedy than that 

 of the legs ; and the fingers are sooner separat- 

 ed than the toes. About this time the internal 

 parts are found, upon dissection, to become dis- 

 tinguishable. The places of the bones are mark- 

 ed by thread-like substances, that are yet more 

 fluid even than a jelly. Among them the ribs 

 are distinguishable, like threads also, disposed on 



