PHILIPPINE MACROUROID FISHES—GILBERT AND HUBBS. 435 
superior rostral sensory canal by means of a foramen, which is 
roofed over by a bony arch forming the anterior part of the oc- 
cipital ridge. From the upper edge of the high median rostral 
crest of each side there branches off a slender horizontal rod, which 
supports the skin over a large sense organ. 
The position of the anus is more posterior than in other species; 
its distance from the base of the ventral fin, 1.95 (1.8 to 2.3) in 
head; its distance from the isthmus, 1.16 (1.15 to 1.32). The dis- 
tance between the base of the outer ventral ray and the isthmus 
is contained 2.7 (to 3.0) times in the head. 
A highly differentiated organ, of problematic function, lies in 
the body wall on the midabdominal line. It is probably homolo- 
gous to, but more complicated than, similar structures which we 
have described in Coelorhynchus and in other genera. As we have 
found this organ with skeletal support only in this subgenus (Qwin- 
cuncia), its structure is probably diagnostic of the group. A de- 
scription of this organ follows. A black superficial streak extends 
forward from the anus, at each end dilated into an area in which 
the scales are much reduced in size. The distance between the ante- 
rior end of this black streak and the isthmus is a little greater than 
half the orbital length. Immediately above this streak, between 
the ventral ends of the lateral muscles, there is located the organ 
being described. It consists of a stand of soft tissue, more or less 
pigmented on its ventral (or outer) surface, firmly united with 
the peritoneum, and expanded at each end into a depressed dilation. 
The posterior ane is bilobed, being divided by the anus. The thick 
anterior dilation is roughly triangular in outline, with a convex 
anterior edge. It lies within a cavity, and is supported in a strik- 
ingly peculiar manner by a cartilaginous rod in close connection 
with the pelvic girdle. The posterior arm of this bone is a poorly 
ossified plate, which by meeting its fellow at the median line, forms 
a brace directly between the ventral bases. From the anteromedian 
angle of each of these posterior limbs a cylindrical rod of cartilagi- 
nous tissue extends forward to the sides of the anterior dilation, 
from which it extends dorsad, meeting its fellow in a wide arch, 
the apex of which is bound to the well ossified anterior arms of 
the public bone, where these meet at the median line. 
Nine pyloric caeca, much shorter than the orbit, were counted in 
one specimen. 
Shrimp-like crustaceans were found in the stomachs of two speci- 
mens. 
The lateral line gently rises anteriorly to form a long, low curve, 
the chord of which is about as long as the distance between the anus 
and the isthmus. The thin scales are armed with short, stout, sub- 
erect spinules, which are arranged in quincunx order (occasionally 
showing a tendency to align themselves to form parallel or divergent 
