NERVOUS SYSTEM. VERTEBRATA. 209 



On the mesial surface of the hemisphere there is a sulcus 

 which may possibly represent a highly placed calcarine, 

 which has become prolonged forward after the manner of 

 the so-called " splenial " sulcus of Krueg in most mammals. 



The appearance of the diminutive corpus callosum (c.C.) 

 and the large hippocampal commissure (PS.D., PS.V.) and 

 anterior commissure (A.C.) are shown diagrammatically in 

 the accompanying scheme (fig. 78), which also exhibits the 



Fiff. 78. 



PS.D.. 



relations of the fornix or fimbria (F), the fascia dentata 



(F.D.), hippocampus nudus (N.H.), and vestigial hippo- 



campus (V.H.) to the commissures and precommissural 



area(p). 0. C. 1323 i. 



Elliot Smith, Trans. Linn. Soc. (2nd Series, Zool.) 



vol. vii. 1899, p. 297. 



D. 268. The brain of a Cabassou (Cabassous unicinctiis). 



This is an excellent example of a simple, highly macros- 

 matic brain essentially similar to that of the Six-banded 

 Armadillo, but relatively much shorter and broader than 

 the latter. 



The large olfactory bulbs are flattened against the anterior 

 surface of the short cerebral hemispheres (figs. 79, 80, 81). 



The posterior rhinal fissure is represented only by a very 

 shallow depression (Hg. 80), but the supposed representative 

 of the orbital sulcus is exceedingly well developed (figs. 79 

 and 80). 



The representative of the sulcus 8 of Dasypus is much 

 more insignificant in Cabassous (figs. 79 and 80) than it is 

 in the former. 



VOL. it. P 



