S'lTOV dl'^ r.KATXS OF SIX KMIM'AT SCI KNTllSTS AND SCIIOLAKK. 263 



length, ([uite tortuous and likewise of similar couioruiation to that of Joseph Leidy. 

 The subfrontal is apparently (hvided into two segments, of which the cephalic one 

 joins the radiate fissure. 



Mesal Surface. — The supercallosal proper is shortened b}' the intervention of an 

 oblique isthmus joining the superfrontal and callosal gyres as is commonly observed in 

 cases of so-called " duplication of the (old) calloso-marginal." The paracentral fissure 

 is markedly tortuous and ramified. The rostral fissure anastomoses with the fronto- 

 marginal-supercallosal piece and cuts across the hemicerebral border. 



Orbital Surface. — The orbital fissure is a simple zygal fissure. The olfactory is 4 

 cm. in length. 



Gyre-'i of the Fronfid Lobe (Lateral Surface). — The precentral gyre is somewhat 

 wider and of simpler configuration than that of the left side. The superfrontal is of 

 good size and very much resembles that of Joseph Leidy's right hemicerebrum. The 

 medifrontal gyre is rather larger, the subfrontal a trifle smaller as compared with those 

 of the left side. 



The mesal surface is not so clearly divided into three tiei's except where the 

 supercallosal fissural segments overlap in parallel. The paracentral gyre is smaller 

 and of irregular shape. The callosal gyre is quite broad just ventrad of the pai'a- 

 central and is marked by a short medicallosal fissure. 



Orbital Surface. — The mesorbital gyre is a trifle less wide and the general surface 

 is less complexly marked than on the left side. 



The postorbital limbus is somewhat more marked on this side. 



Fis.sures of the Parietal and Occipital Lobes {Lateral Surface). The Postcentral Fis- 

 sural Comple.v,. — The postcentral, subcentral, parietal and' intermedial (thence super- 

 temporal) fissures anastomose within a small area in a way that is in many respects 

 similar to the confluence of these fissures in the left half of Joseph Leidy's cerebrum. 

 The subcentral is continuous with the transpostcentral dipping into the sylvian cleft 

 on the left side. The tendency to transverse fissuration has abbreviated the parietal 

 fissure considerably and it is separated from the paroccipital I33' an isthmus. The 

 paroccipital is of irregular zygal shape with numerous rami. The exoccipital complex 

 in this case shows a well-defined ''sulcus lunatus " (Elliot Smith) and a prelunate 

 ramus. 



Mesal Surface. — The precuneal fissure is of markedl}? irregular Z3'gal type. Two 

 fissures mark the cuneal surface, one already described as joining the occipital fissure, 

 the other anastomosing with the calcai'ine. 



Gyres of the Parietal and Occipital LoIhx (Latend Surface). — The postcentral gyre 

 is of good width in its dorsal two-thirds l)ut quite nai'row ventrad of this. The parietal 



