XII 



PHYLUM CHORDATA 



527 



9. Primates, comprising the lemurs, apes, and monkeys, 

 and the human species. 



The two genera of the Prototheria, Ornithorhynchus and 

 Echidna, differ somewhat widely from one another in gen- 

 eral appearance. The former (Fig. 314) has the surface 

 covered with a close soft fur, and has the upper jaw pro- 

 duced into a depressed muzzle, not unlike the beak of a 

 duck, covered with a smooth, hairless integument. The eyes 

 are very small, and there is no auditory pinna. The legs are 



Fig. 315.— Spiny Ant-eater {Echidna acitleata). (After Vogt and Specht.) 



short, and the five digits end in strong claws, and are con- 

 nected together by a web, so that the limbs are equally 

 adapted for burrowing and for swimming. The tail is elon- 

 gated and depressed, covered with fur. The male has a 

 sharp-pointed, curved spur on the inner side of the foot, 

 having the duct of a poison-gland opening at its apex. 

 Echidna (Fig. 315) has the body covered above with 

 strong-pointed spines, between which are coarse hairs ; the 



