406 J. J. KEEGAN 



respectively, but these figures are unreliable on account of the 

 pathological condition of the left hemisphere, which had de- 

 stroyed a part of the temporal lobe. This hemisphere also was 

 distorted in preservation, due to the softened condition of the 

 cerebral tissue, consequently no measurements of any value of 

 lengths or indices could be made. Such measurements were 

 established by Cunningham ('92) but have not proven of com- 

 parative value even in perfectly preserved brains. 



The general type of fissuration presented nothing very unusual, 

 gi^'ing the impression of a fairly well and evenly fissured cere- 

 brum. There was no undue prominence of any region, perhaps 

 a greater tendency to a vertical course of the sulci of the central 

 region of the right hemisphere and a tendency to irregular 

 fissuration in the posterior parietal region of the left hemisphere. 

 There was no indication of an exposure of the insula. 



The following brief account of the sulci and gyri is not intended 

 as a description of all points observed, for many of these of no 

 recognized significance or variation can be determined equally 

 as well by an examination of the accompanying figures. These 

 illustrations were made by tracing from photographs and subse- 

 quently inking in the fissures by careful examination of course, 

 depth and bridging gyri. The depth of the more important 

 fissures is entered in the drawing. In general the heavier lines 

 indicate the deeper fissures. A bridging gyrus is indicated by 

 an interruption of the line and an intervening dot. The cortical 

 areas are filled in with different symbols, the plan being to place 

 no two of similar type adjoining. 



These areas were determined by placing those first in which 

 there could be little doubt of their boundaries. The area striata 

 was delimited by macroscopic examination of knife sections. The 

 remaining areas generally could be filled in by a process of elimi- 

 nation, but in some cases they were determined by arbitrary judg- 

 ment. This latter is very evident in cases where the boundary 

 does not correspond to a fissure, but it is surprising how little is 

 left to the judgment and how easily the area conformation can 

 be made to agree with the plan of E. Smith without violating 

 the rule of the deeper fissures being in the main bounding fis- 



