EMBRYOLOGY. 



727 



the mouth. The view he has taken is probably due to the feet that the young 

 sea-urchins from which he made his drawings were compressed. Having fol- 



FlG. 61. 



Fig. 62 



Fig. 65. 



lowed the mouth in the different stages which have been represented here, I 

 think there can be but little doubt that Miiller was mistaken. Compare 

 PI. X. f. 3 of this Review with his Fig. 3, Plate VII., first Memoir, and we 



