XII 



PHYLUM CHORDATA 



521 



the foot, having the duct of a poison-gland opening at its 

 apex. Echidna (Fig. 290) has the body covered above 



with strong, pointed spines, between which are coarse hairs ; 

 the lower surface is covered with hair only. The jaws are 

 produced into a rostrum which is much narrower than that 



