60 . Encephalic Anatomy of the Races 
ORBITAL SURFACE.—The orbital surface may be divided into pre- and post. 
orbital regions, fairly well supplied with fissures of irregular types. The 
mesorbital gyre is unusually narrow. 
FISSURES OF THE PARIETAL AND OCCIPITAL LOBES (LATERAL SURFACE).— 
The Postcentral Fissural Complex.—The postcentral and subecentral pieces 
in this instance anastomose over a vadum to form a continuous fissure 
whose total length is 8 em. The postcentral segment is the longer. It is 
fairly tortuous, and terminates dorsally in a furcal manner to embrace 
the caudal limb of the paracentral. Caudally it anastomoses with the 
parietal by two junctions. Its junction with the subcentral takes place 
at a depth of 10 mm. over an oblique subgyre. The subcentral itself is 
tri-radiate. The transpostcentral is independent. 
The parietal is a deep and well-marked fissure which anastomoses with 
the postcentral by means of two limbs, enclosing a gyral islet. It is the 
ventral one of these limbs which is deeper, and which is the ideal con- 
tinuation of the fissure. One ramus of the parietal is sent into the 
parietal gyre, another into the angular. Caudad it anastomoses with the 
cephalic paroccipital ramus. There is a long transparietal which is con- 
fluent with the precuneal fissure on the meson. A second transparietal, 
tri-radiate, lies in the caudal part. 
The paroccipital is zygal, with simple stipes and a bifurecating caudal 
ramus whose mesial limb is very long. 
The intermedial proper is 2.3 em. in length, independent of other fissures 
and its ventral end fureal. What may be described as a second inter- 
medial (also named ‘“‘ angular fissure” by some authors) (ITMUL”, Figure 
13) lies caudad of the supertemporal, demarcating the angular from the 
postparietal gyre, and running into the anastomosing fissure which joins 
the supertemporal and “ exoccipitalis secundus ” (EOP”, Figure 13). 
In the parieto-occipital transition there exist several fissures which 
have the value of exoccipital segments. One of these (EOP’) is a small 
tri-radiate piece. Another larger longitudinal piece (EOP”) anastomoses 
cephalad with the supertemporal. Ventrad of this is a third segment 
marked (?) which is confluent with the postcalearine. 
MESIAL SURFACE.—The precuneal is of the usual zygal shape. The dorsi- 
cephalic limb anastomoses with the transparietal. The cuneal fissure is 
short. The posteuneal is a distinet, tri-radiate fissure. 
GYRES OF THE PARIETAL AND OCCIPITAL LOBES (LATERAL SURFACE).—The 
postcentral gyre is of a simple contour, and rather narrow in its dorsal 
third; ventrad it is broader. The parietal gyre is of good size, wide, and 
well fissured. The paroccipital gyre is small. The marginal and angular 
gyres are much simpler than in the other brains and relatively smaller. 
MesIAL SuRFACE.—The precuneus is large and presents a richly-fissured 
surface. The cuneus is small and of rather a simple configuration. The 
hippocampal gyre is quite narrow. 
FISSURES OF THE TEMPORAL LOBE (LATERO-VENTRAL SURFACE).—In this 
hemicerebrum the supertemporal fissure is interrupted at a distance of 3 
cm. from the temporal pole by a narrow isthmus. The cephalic segment 
is quadri-radiate. The longer piece attains a length of 8.5 em., and anas- 
