1910.] The Insectivora and TUlodontia. 231 



2. Infraclass Monodelphia de Blainville (Placentalia Bonaparte, Eutheria 



Hiixley). 



No epipvibic bones; a corpus callosuni; angle typically not inflected; 

 all the antemolar teeth typically represented by both milk and perma- 

 nent teeth; pf typically present; molars typically |^. 



CHAPTER V. GENETIC RELATIONS OF THE INSECTIVORA 



AND TILLODONTIA. 



Anabj.sis. 



Page. 



Outline History of the Classification 231 



The Zaiambdodonta 236 



The Centetidfp 236 



Are the molars of the Centetidse "pseudotritubercular"? 236 



The Solenodontida? 240 



Notes on the Comparative Osteology of Solenodon ixiradoxus 241 



Phyletic interpretation of the osteological characters of Solenodon . . . 253 



The ChrysochloridiP, not related to Notoryctes 255 



The Necrolestida? 259 



The Erinaceoidea 260 



The Leptictidi? 260 



The Erinaceidffi ■ 262 



The Soricoidea 263 



Genetic interrelations of the Lipotyphlous Insectivores (Summary) .... 264 



The Menotyphla 268 



The TupaiidiE 269 



Phyletic interpretation of the more important characters of the Tupaiidse 279 



The Macroscelididffi 280 



Phyletic interpretation of the more ii\iportant characters of the Macro- 



scelididiE . . 283 



Genetic relations of the Menotyphla 284 



The Tertiary History of the Menotyphla 285 



"Marsupial" characters in the Insectivora 286 



Speculations on the origin of the order Insectivora 287 



The Tillodontia 292 



Outline History of the Classification. 



1693. Ray groups the hedgehog, armadillo, mole, shrew, tamandua, bat 

 and sloth in the "quadrupeda pede multifido vivipara, rostro productiore 

 anomala: ac primo dentata." 



