On the Baculum of come Genera of Muafcelidae. M7 



name. Bat tliat he later realized its peculiarity is proved 

 by his having written on the typical skin a special generic 

 name, no doubt intended for ultimate publication. 



I. Ntbsoryctes, g. n. 

 Genotype. N. tetradactylus {Oryzoryctes tetradactylus, 

 M.-Edw. & Grand.). 



No other species known, as 0. niger, Maj., appears to me 

 to be merely a melanism of A 7 ", tetradactylus. 



Very like Oryzorictes in most respects, but not quite so 

 highly modified for a fbssorial life and with only four tore- 

 claws. Its fur is like that of other members of the group, 

 and not modified into the velvety condition of that of the 

 Talpidse, as is the case in Oryzorictes. The skull also is less 

 markedly ridged and broadened behind than in that geuus, 

 nor is it so expanded at the tip of the muzzle. 



No special differential characters in the teeth. 



It may be here recorded that both Microgale coivani and 

 Nesoryctes tetradactylus possess a baculum in the penis. 

 The presence of this bone has been recorded in the larger 

 Tenrecidse, but no other Insectivores possess it. 



The bone in Nesoryctes is a simple slightly curved spicule 

 G mm. in length, thickened at the proximal end. 



5. Oryzorictes, M.-Edw. 



Oryzoryctes, Tiouess. (emend.). 



Genotype and only species. 0. hova, M.-Edw. 



XXXY. — The Baculum or Os Penis of some Genera of 

 Mustelidse. By R. I. Pocock, F.K.S. 



Mr. Oldfield Thomas's paper upon the os penis — or the 

 baculum, as he appropriately names it — of the Sciuridae shows 

 that this bone, at least in the case of those rodents, has a quite 

 unexpected value, greater than that supplied by the skulls 

 and teeth, in determining the affinities of the genera. Very 

 possibly it has a similar systematic importance in other 

 groups of Mammalia, and deserves, in consequence, more 

 attention than has hitherto been given to it by osteologists. 



As has long been known, this bone is especially well 

 developed in the Arctoid and Cynoid Carnivora. It has been 



