Edward Anthony Spitzka 5 
-~? 
to call it—seems as distinctive of the Eskimo-type as it is seen, better 
developed, in the brains of “ Atana,” “ Nooktah” and “ Kishu,” and 
places it in this category as differing from all other types, quite as the 
outward characteristics of the race itself do. 
LEFT HEMICEREBRUM. 
Tue INTERLOBAR FissuRES.—The Sylvian Fissure and its Rami.—The sylvian 
fissure is 5 em. in length, fairly sinuous, opening out cephalad into a dis- 
tinet sylvian fovea at the bottom of which the insu4a is visible. The 
depths of the fissure are aS follows: Presylvian depth, 11 mm.; medi- 
sylvian depth, 18 mm.; postsylvian depth, 21 mm. 
The basisylvian is 20 mm. deep. The presylvian, as determined by its 
origin from the extreme dorsi-cephalic angle of the insula, is 12 mm. in 
length and simple. The subsylvian is of the same length. The episylvian 
is somewhat Z-shaped and 1.5 cm. in length. The hyposylvian is well- 
marked and of the same length. 
Central Fissure—The central fissure is 11 em. in length, of the usual 
contour, anastomosing over a vadum with a precentral-medifrontal seg- 
ment. It has four short rami, two cephalic, and two caudal. 
Occipital Fissure.—The occipital fissure attains a mesial length of 3 cm., 
and a dorsal length of 1.5 em. It is deep throughout and of a simple con- 
tour. One short ramus is sent into the cuneus, another indents the par- 
occipital gyre cephalad. 
Calcarine Fissure——The calearine is an exceedingly simple, slightly-curved 
fissure, 3 cm. in length. It is separated from the postcalearine by a nar- 
row but distinct transcalearine isthmus. The postcalearine begins on 
the mesial surface in a fureal piece and is continuous with a fissure 
(marked by (?) in Figure 13) upon the ventro-lateral margin of the hemi- 
cerebrum, the whole attaining a length of 7 cm. 
The oceipito-calearine fissural stem is simple, 3 em. in length, and is 
joined superficially by an independent fissure in the precuneus. 
FISSURES OF THE FRONTAL LOBE (LATERAL SURFACE).—The Precentral Fis- 
sural Complex.—The supercentral is 4 em. in length, and unusually simple, 
running parallel with the central. From its middle springs the super- 
frontal. Ventro-cephalad of the supercentral and separated from it—lies 
a segment which partakes of the values of a medifrontal and a precentral 
piece, and corresponds to what Schifer (Quain) describes as an “ anterior 
ramus of the inferior precentral.’”’ This piece is peculiar in that it is not 
confluent with the precentral, but anastomoses across the precentral gyre 
to join the central fissure over a vadum. The third segment is the pre- 
central proper, 3.5 cm. long, from which springs the subfrontal. 
The diagonal fissure in this case presents a curious appearance. The 
fissure is exceedingly deep and opens freely into the sylvian fovea. It 
completely divides the subfrontal gyre, being deeply confluent with the 
subfrontal fissure dorsally. Both walls of the fissure are again marked by 
smaller fissures and grooves. : 
