96 



THE GENESIS OF SPECIES. 



[CHAP. 



allied to the sloth, namely, the great ant-eater (Myrme- 

 cophaga), we have again an ornithic character in its horny 

 gizzard -like stomach. In man and the highest apes the 

 cascum has a vermiform appendix, as it has also in the 

 wombat ! 



Upper Figure ANTECHINTJS MINTTTISSIMIJS (implacental). 

 Lower Figure Mus DELICATULUS (placentat). 



Also the similar forms presented by the crowns of the 

 teeth in some seals, in certain sharks, and in some extinct 

 Cetacea, may be referred to ; as also the similarity of the 

 beak in birds, some reptiles, in the tadpole, and cuttle- 

 fishes. As to entire external form, may be adduced the 

 wonderful similarity between a true mouse (Mus ddicatu- 

 lus) and a small marsupial, pointed out by Mr. Andrew 



