36 Encephalic Anatomy of the Races 
serve mention. One of these has been described as anastomosing with the 
precentral. Another springs from the orbitofrontal and joins the super- 
frontal. 
The subfrontal fissure is of unusual form. Arising from the neighbor- 
hood of the cortical islet at its junction with the diagonal and an anasto- 
mosing ramus of the precentral, the fissure sweeps rather far dorsad, to 
end in a hook-like manner about 2.5 em. cephalad of its caudal origin. 
Dorsad the fissure anastomoses with the superfrontal. 
The orbitofrontal is distinct, about 3 em. in length and is joined by a 
smmedifrontal segment. 
The radiate fissure is simple, 2.3 em. in length and anastomoses with a 
tri-radiate (intra-subfrontal) fissure dorsad. One other fissural element 
curves around the cephalic hook of the subfrontal (Figure 1). 
MESIAL SURFACE.—The supercallosal is 8.5 em. in length, and freely con- 
fluent with the paracentral. Numerous rami springing from it traverse 
the mesial surface of the superfrontal gyre 
The paracentral fissure is very irregular, sends off several rami, and is 
confluent with a transparietal fissure as well. The cephalic limb is short. 
The caudal limb just reaches the dorsi-mesal margin. One intrapara- 
central ramus is particularly long. ; 
The inflected fissure is distinct and independent. Its dorsal length is 
15 mm.; mesial length, 13-mm. Its direction is practically perpendicular 
to the dorsi-mesal border on both surfaces. Its lateral end is embraced 
within the dorsal fork of the supereentral. Mesially, its relations are, as 
usual, caudad of the cephalic paracentral limb. 
The rostral fissure is well-marked, 4.5 em. in length, and bifurcated 
cephalad. There is no subrostral. The fronto-marginal is represented by 
but one segment. 
ORBITAL SURFACE.—The orbital fissure resembles a reversed letter K (4) 
in shape, with numerous ramifications (see Figure 4). 
The olfactory fissure is 5 em. in length,.and of simple form. 
GYRES OF THE FRONTAL LOBE (LATERAL SURFACE).—The postcentral gyre 
is of bold contour throughout, and generally wider than the precentral. 
Its connection with the sukfrontal gyre is interrupted, as before de- 
seribed, by the confluence of the precentral and transprecentral fissures. 
The superfrontal gyre is quite large and richly fissured. There is some 
uncertainty as to its lateral limits in the prefrontal region, owing to the 
tendeney to transverse communications amongst the various frontal fis- 
sures. 
The medifrontal gyre is of greater width caudad than cephalad, and 
contains three small independent fissural segments. There is, however, 
not a very marked tendency toward a longitudinal subdivision of the gyre 
into two tiers. 
The subfrontal gyre is of unusual width, owing to the high sweep of its 
limiting fissure—the subfrontal. Its configuration is rendered exceed- 
ingly complex by numerous more or less transversely directed fissures and 
ramifications (Figure 1). 
MerstaAt SurrACE.—The mesial surface of the superfrontal gyre is wide, 
richly fissured by transverse pieces. The callosal gyre is more simple, and 
is marked by several rami of the precuneal, supercallosal and paracentral. 
