NERVOUS SYSTEM. VERTEBRATA. 167 



D. 202. The right cerebral hemisphere, the caudal part of the left 

 cerebral hemisphere, and the brain-stem and cerebellum 

 of a Tasmanian "Wolf" (Thylacinus cynocephalus). 



The mesial aspect of the hemisphere (fig. 48) presents 

 the typical arrangement of the cerebral commissures and 

 hippocampus ; and, as such, this identical specimen was 

 figured by the late Sir William Flower (Phil. Trans. 1865). 



Fig. 48. (xf.) 



COMM.D.. 

 FASG.DENT 



FASC . DENT. 



HIP. F. 



COMM.V. OPT. CHI. 



He, however, erroneously regarded the dorsal commissure 

 as a true corpus callosum. There is a well-developed 

 calcarine sulcus beginning just above the caudal extremity 

 of the rhinal fissure. It is prolonged upward and forward 

 after the manner of the splenial complex in many orders. 

 An oblique section has been made through the left hemi- 

 sphere (fig. 49) (in the plane indicated in fig. 48) in the 



Fig. 49. (x.) 



- -- -^ _.- CALCAR 

 SULC CALC.JS, 



region of the deepest part of the calcarine sulcus. The 

 latter is thus shown to be "complete" or "total"; in 

 other words it gives rise to a bulging the calcar avis or 

 so-called hippocampus minor in the ventricle immediately 

 to the peripheral side of the true hippocampus. 



There is a deep and sharply-defined rhinal fissure, acutely 

 bent at the junction of its anterior and posterior parts 



