572 



ZOOLOGY. 



the cloaca, as in birds. The sternum articulateswith a free cora- 

 coid, and an inter-clavicle and epicoracoid bone are present. 



The brain differs from that of the members of the higher sub- 

 classes.* Echidna lays large eggs, 2 cm. long, placing them 

 * The hind skull is intermediate between that of Amphibians and 

 higher mammals. (Parker.) 



