KTUDY OF BRAINS OF SIX EMINENT SCIENTISTS AND SCHOLARS. 261 



Orbital Surface. — The orbital fissure is quite complexly ramified. The olfactory 

 fissure is 4 cm. in length. 



Gt/res of the Frontal Lobe (Lateral Surface). — The precentral gyre is sinuous and 

 of lesser width than its fellow on the right. The superfrontal is of moderate width. 

 The medifrontal is quite extensive and complexly marked by the medifrontal fissure 

 with its numerous branches. The perfect continuity of the medifrontal fissure tends 

 to produce the " four-tier type " of frontal lobe in one portion at least. The sub- 

 frontal gyre of this side is more distinctly demarcated than its fellow on the right. 

 (Compared with that of Joseph Leidy it is relatively smaller.) 



The mesal ■■surface is quite definitely divided into three tiers by the concentric and 

 fairly distinct supercallosal and frontomai'ginal fissures. The paracentral gyre is of 

 good size and regular shape. The frontal portion of the callosal gyre is quite simple 

 and only slightly marked by a medicallosal groove. 



Orbital Surface. — The left mesorbital gyre is broader than that of the right. The 

 rest of this surface is quite cemplexly marked by the much-ramified orbital fissure. 

 A postorbital limbus is present. 



Fissures of the Parietal and Occipital Lobes {Lateral Surface). The Postcentral 

 Fissural Complex. — The dorsal postcentral segment is a wholly independent zygal 

 fissure of limited extent. The subcentral is directly continuous with the parietal 

 fissure and anastomoses with the transpostcentral dipping into the sylvian cleft. 



The parietal fissure is 4.5 cm. in length and anastomoses caudad with the paroc- 

 cipital, ventrad Avith the supertemporal. There is a T-shaped transparietal commu- 

 nicating at the dorsi-mesal margin with the intraprecuneal. The paroccipital is of 

 the usual zygal shape. 



Mesal Surface. — The precuneal fissure is irregularly zygal and anastomoses with 

 the paracentral and intraprecuneal fissures. The adocciijital fissure has been men- 

 tioned in the description of the occipital fissure. There are well marked cuneal (tri- 

 radiate) and postcuneal (quadri-radiate) segments in the cuneus. 



Gyres of the Parietal and Occipital Lobes {Lateral Surface). — The postcentral gyre 

 is much wider than the precentral. The parietal gyre is wider than its fellow on the 

 right ; the paroccipital is also larger and of simpler appearance. The marginal and 

 angular gyres are all massive and complexly marked. 



Blesal Surface. — Both cuneus and precuneus are of good size, especially the 

 latter, and the fissural markings are quite intricate. 



Fissures of the Temporcd Lobes {Latero-ventral Surface). — The supertemporal fissure 

 presents a markedly tortuous course and seems to be made up rather of connected 

 zygal segments, in this respect very much resemVjling the brain of .Joseph Leidy. 



