202 STUDY OF F.KATNS OF SIX EXIXFNT SCIENTISTS ANT) SCHOLARS. 



Caudally it anastomoses deeply with the parietal and a meditemporal segment. The 

 meditemporal is represented by two z^^gal segments. The subtemporal is more clearly 

 defined and of a good length. The collateral fissure is 10 cm. long. The postrhinal 

 is barely indicated. 



Tlic gi/rcs of tlie temporal lobe are notable for their complex and irregularly tor- 

 tuous conformation. The subcollateral is of considerable width. 



The Insulse. — It was not practicable to examine the insulae thoroughly owing to 

 the fragility of the specimen. The depths of the sylvian cleft on both sides are as 

 follows : 



Lett. Right. 



Pre sylvian depth ........ 12 13 



Medi-sj'lviau depth is 23 



Post-sylviau depth 31 ;{1 



Riyld Hemicerebrum. The Jnferlobur Fissures. The Si/lvkin Fissure and its Tlaiui. — 

 The length of the sylvian fissure is 4.5 cm. The sylvian angle is 18°. The depths are 

 as follows: Pre-sylvian, 13 mm.; medi-sylvian, 23 mm.; post-sylvian, 31 mm. The 

 pre-sylvian ramus is 2 cm. in length, the subsylvian about the same. The episylvian 

 ramus is more vertical in direction than that of the left side. The hyposylvian is 

 merely indicated by an incisure. 



The Centra} Fissure. — The length of the central fissure is 9.5 cm. and it is less 

 sinuous and less ramified than the left central. It does not anastomose with any of 

 the neighboring fissures. 



Ihe (Jccipitid Fissure. — The length on the meson is 3.3 cm. ; on the convex sur- 

 face, 1.5 cm. It is joined by a well-marked cuneal fissure which gives the occipital 

 an appearance of bifurcation. The occipital angle approaches 65° ; this is due to the 

 more caudal situation of the occipito-calcarine junction as compared with the left side. 

 77?e Cnlcarine Fissure proper is 4 cm. in length. A slight vadum separates it 

 from the postcalcarine, a triradiate fissure situated well upon the occipital pole. The 

 occipito-calcarine stem is over 3 cm. in length and almost totally traverses the hippo- 

 campal gyre. 



Fissures of the Frontal Lobe [Lateral Surface). The Precentral Fissural Comjde.r. — 

 The supercentral fissure is of zygal shape and directh' continuous cephalad with the 

 superfrontal ; a well-marked paramesial with long transverse caudal rami closely ap- 

 proaches the former fissure. The precentral is well marked and sends off a long 

 "anterior precentral" ramus. 



The superfrontal runs well cephalad and presents a marked resemblance to the 

 same fissure in the right half of .Joseph Leidy's brain. The medifrontal is 7 cm. in 



