STUDY OF BRAINS OF SIX EMINENT SCIENTISTS AND SCHOLARS. 283 



tral and inflected fissures, and its surface is marked by one vertical and one longitu- 

 dinal intraparacentral segment ; the latter is confluent with the caudal paracentral 

 limb over a vaduni. 



That part of the callosal gyre which is cephalad of the precuneus, aside from the 

 medicallosal fissure described above presents nothing unusual. 



Orbital Surface is slightly concave, fairly well fissured and of rather broader 

 expanse than on the left side. The mesorbital gyre is quite narrow. The remainder 

 of this surface tends more to sagittal than to transverse division. 



A certain peculiarity observable on this surface consists in the formation of a 

 prominent eminence in the form of a limbus which is in apposition to the temporal 

 apex as if struggling for the occupation of the middle fossa of the skull. This forma- 

 tion, to which I venture to give, provisionally, the name " postorbital limbus" 

 is demarcated by a distinct incisure in which the wings of the sphenoid bone were 

 received. As a result of this protrusion of the orbital parts into the middle fossa, the 

 basisylvian fissure necessarily falls below the margin of the sphenoidal wings instead 

 of being just at it. This is best seen in Fig. 2. 



I find but one description in literature of a similar peculiarity, given by Retzius 

 in "Das Gehirn eines Lapplanders." * The limbus is shown in Wagner's plate of 

 Gauss's brain, and the writer has since observed it in a Japanese brain.f 



FissuRES qf the Parietal and Occipital Lobes (Lateral Surface). Tlie 

 Postcentral Fissural Complex. — The postcentral boundaries are quite unusual and 

 atypical. Instead of the usual long postcentral, only a small furcal segment is repre- 

 sented, embracing the caudal limb of the paracentral. The subcentral segment is also 

 short and joins the parietal. Between the postcentral and subcentral lie two unnamed 

 fissures ; of these one runs obliquely across the postcentral gyre. The transpostcentral 

 rises deeply from out of the sylvian cleft and divides into two rami. 



The parietal fissure is deep and passes without interruption from the subcentral 

 to become confluent with the paroccipital. In its course it sends off several short rami 

 and joins the second (caudal) intermedial {itml", Figs. 1 and 3). A transparietal 

 (Brissaud) 4.5 cm. in length marks the parietal gyre. 



The paroccipital is of the usual zygal form (Fig. 7) and is peculiar in that its 

 cephalic stipe joins the occipital. The parietal joins the cephalic ramus, while the 

 other paroccipital branches are free from anastomoses. 



It remains to describe the two intermedials. The cephalic one {itml'), demarcating 

 the marginal gyre from the angular, is a very small furrow : the caudal one (itml"), 



*Retzins, Inlernnt. Beilrdge z. Wiss. Med., I, p. 41, 1891. 



fE. A. Spitzka, American Journal of Anatomy , Vol. II, 1903; Pbiladelpbia MedicalJonrnal, April 11, 1903. 



