Pish, Brain of the Fur Seal. 6y 



with the cruciate. It is separated by a gyre 4 millimeters in 

 width. The fissure passes ventro-caudally and a little beyond 

 the splenium on the ventral aspect and it apparently terminates 

 in a wide fork, or else enters a fissure passing at right angles to 

 its own course. Sounding the fissure at this point gives some 

 indication of a shallow separating the caudal branch of the fork. 

 Following the appearance designated by Krueg in his diagrams 

 of the conditions found in some of the carnivora, the splenial 

 proper includes the ventral branch of the fork, while the dorsal 

 branch may represent what he calls the postsplenial. On the 

 left hemicerebrum the splenial fissure penetrates the hemice- 

 rebral margin and appears for a short distance on the dorsal sur- 

 face. A smaller but well defined fissure lies in front of the 

 splenial. On the left side it cuts the dorsal margin. For the 

 present we may designate it as the presplenial fissure. It cor- 

 responds very well with the fissure which Kiikenthal has called 

 fissura sublimica anterior. 



The Marginal or supersplenial just passes the meso-ventral 

 margin of the hemicerebrum about ten millimeters caudad of the 

 splenial. It extends approximately parallel with it to the dor- 

 sal margin which it cuts and on the right hemicerebrum extends 

 on the dorsal surface for about 15 millimeters. On the left 

 hemicerebrum the fissure branches just at the margin. The 

 main portion however continues obliquely latero-cephalad for 

 about 20 millimeters. In the gyre between the splenial and su- 

 persplenial fissures a well represented secondary fissure is seen. 



A well defined but unnamed fissure lies on the meso-ven- 

 tral surface. It arises at the caudal margin and proceeds in an 

 angular course toward the ventral end of the splenial, it then 

 swerves cephalo-laterad and terminates not far from the post- 

 rhinal. Its position corresponds approximately to the collateral 

 fissure in the human brain. This tentorial surface of the cere- 

 brum has numerous secondary fissures and branchings some of 

 which seem large enough to merit special mention. One such 

 fissure lying parallel with the postsplenial suggests a similarity 

 to the occipital. It cuts the hemicerebral margin slightly and 

 the relation of the lateral fissure at this point suggests in a way 



