THE SIXTH WEEK. 



503 



The fingers project beyond the margin of the hand by the 

 middle of the sixth week ; and the toes become clearly esta- 

 blished, although they do not reach the margin of the foot until 

 the early part of the seventh week. The elbow and knee project 

 outwards at first, but towards the end of the sixth week the limbs 



FIG. 211. -Human Embryo about the middle of the sixth week. 

 (From His.) x 5. 



become rotated so as to lie alongside the body, the elbow being 

 directed backwards, and the knee forwards. 



The tail is less conspicuous than before, and owing to the 

 growth of adjacent parts is gradually becoming incorporated in 

 the body. 



7. The Second Month. 



At the end of the second month the embryo measures from 

 25 to 30 mm. in length, and weighs from 12 to 20 grammes. 



The cervical flexure has almost disappeared : the head is 

 well lifted up, and is still of very large size, forming nearly half 

 the entire embryo. The eyelids, nose, lips, and external ear 

 have all made considerable advance ; the nose is still broad 

 and flat, and the nostrils wide apart, though much closer than 



