NERVOUS SYSTEM. VERTEBBATA. 



171 



the simplicity of the cerebellum, and its markedly-projecting, 

 pedunculated floccular lobes clearly show that it is the brain 

 of Perameles. In fact, it exhibits the characteristic features 

 of the genus in a much more distinctive manner than the 

 specimen (D. 206) labelled " Perameles." In both speci- 

 mens the large olfactory bulbs are damaged so that their 

 great size is not properly shown. 



The brain of Perameles is even more generalised and 

 simple than that of Dasyurus. It also closely resembles the 

 brain of that most generalised of all Eutherian brains the 

 Hedgehog's in all points except the arrangement of the 

 commissures : for Erinaceus, like all Eutheria, possesses a 

 true corpus callosum. 



Fig. 52. (Nat. size.) 



OLF. BULB. 



The rhinal fissure is shallower and shorter than it is in 

 Sarcopldlus : there is only a faint indication of the orbital 

 (presylvian) sulcus, which closely resembles that of Erina- 

 ceus ; the cerebellum is much simpler, and there are no 

 exposed medullary areas between the mesial and lateral 

 portions of the organ. 



The accompanying drawing (fig. 52) represents the 

 characteristic features of the base of the brain in a fresh 

 specimen. 0. C. 1323 cd. 



Gervais, Nouv. Arch. Mus., t. v. 1869, p. 242. 



[The reader is warned that Gervais' figure 12 on Plate 

 xiii. obviously represents the brain of some small Macro- 

 pod, and not a Perameles as it is labelled.] 



