MONOTREMES 



xix. 9 iviuiNU i K£-iviiiS 555 



short fur, thick tail, and perhaps absence of external ears. The animals 

 burrow in the banks, making nests in which the young are reared. 

 They are not uncommon in the rivers of southern and eastern 



Fig. 329. Brain of the platypus. 



ac. anterior commissure; bo. olfactory bulb; cl. cerebellum; fl. flocculus ; fM. foramen of 

 Munro; hab. habenula; he. hippocampal commissure; hip. hippocampus; hp. hypophysis; 

 ht. hypothalamus; mo. medulla oblongata; ol. optic lobe; on. olfactory nerve; pal. pallium; 

 pV. pons Varolii; pyr. pyriform lobe; tc. tuber cinereum; th. thalamus; to. tuberculum 

 olfactorium; II— XII. cranial nerves. (From Kingsley, Comparative Anatomy of Vertebrates, 

 The Blakiston Company. After Elliot Smith.) 



Australia and Tasmania and fortunately are difficult to catch and 

 therefore in no danger of extinction, though their fur and flesh are 

 both useful. 



Several species of spiny ant-eater are known and they occur in New 

 Guinea as well as Australia. They show specializations for ant-eating 

 similar to those of Myrmecophaga (p. 397), namely, long snout, long 

 tongue, and large salivary glands. The clawed feet are used to make 

 burrows for the young, as well as for digging up the nests of ants. It is 



