Edward Anthony Spitzka 65 
fissures is also much more intricate in configuration. The callosal gyre 
is simple. The paracentral gyre is of the same shape and size as its 
fellow. j 
ORBITAL SURFACE.—The well-marked transorbital fissure distinctly de- 
marcates the postorbital from the preorbital region. The latter is divided 
into several sagittal gyres. 
FISSURES OF THE PARIETAL AND OccIPiTAL LOBES (LATERAL SURFACE).— 
The Postcentral Fissural Complex—In this case the postcentral and sub- 
central elements are separated from each other. The postcentral is tri- 
radiate, with its dorsal and caudal limbs embracing the caudal paracentral 
limb. The longer, ventral limb anastomoses with the parietal. The sub- 
central and transpostcentral are confluent over a deep vadum, and join 
the sylvian. 
The parietal is a tortuous fissure, 4.5 em. in length, and separated from 
the paroccipital. A ventral ramus joins the intermedial and by this the 
supertemporal superficially. A long dorsal ramus traverses the parietal 
gyre. There is a transparietal which crosses the margin to join an intra- 
precuneal. 
The paroccipital is an irregular zygal fissure, independent, but with long 
rami. Its relations to the occipital are difficult to determine with ac- 
curacy. 
There is one distinct exoccipital zygal fissure which anastomoses ceph- 
alad with the supertemporal. A few other irregular, unnamed fissures 
mark this region. 
MeEsIAL SuRFACE.—The precuneal is a simple zygal fissure. Dorsad of 
this there is an intraprecuneal piece which joins both the paracentral 
(over a vadum) and the transparietal. The cuneus is marked by a cuneal 
and a postecuneal fissure, both running parallel with the calearine and 
anastomosing with the occipital. 
GYRES OF THE PARIETAL AND OCCIPITAL LOBES (LATERAL SURFACE).—The 
postcentral gyre is of the same form and size as its opposite fellow. The 
parietal is of moderate size—presenting nothing notable. The paroccipital 
gyre, though small, is curiously marked by transverse pieces. The mar- 
ginal and angular gyres are better developed than those of the left half 
in all respects, the latter being especially massive. 
MEsIAL SuRFACE.—The precuneus is of good size and of the same form 
as that on the left half. The cuneus is fairly well divided into three 
longitudinal tiers by the cuneal and postcuneal fissures. 
FISSURES OF THE TEMPORAL LOBE (LATERO-VENTRAL SURFACE).—The super- 
temporal fissure runs in a fairly straight course till, in the region of the 
angular gyre, it becomes irregular, and turns sharply dorsad. Its total 
length is 12 cm. In its course it anastomoses with the intermedial, and 
thence with the parietal, and further caudad with the exoccipital seg- 
ment. 
The meditemporal is represented by several tri-radiate and two longi- 
tudinal, ramifying segments. The subtemporal is better defined, attain- 
ing a length of 9 em., and anastomosing with one of the meditemporals. 
The collateral is short, and as on the left side there is a separate ceph- 
alice segment. The postrhinal is merely indicated by a shallow groove. 
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