168 
BULLETIN OF THE UNITED STATES FISH COMMISSION. 
are longest, and is comparatively high, the longest rays being nearly two-thirds length of head 
and 5 times length of dorsal spines; the origin of anterior dorsal is 0.4 distance from end of snout to 
base of caudal, that of the posterior dorsal is 0.4 distance from base of caudal to end of snout, and over 
origin of anal. Anal fin large, of 11 branched rays of nearly equal length, rather less than height of 
second dorsal. Pectorals two-thirds as long as head, rounded, with broad base, the central rays 
extending as far as vent; rays 15. Ventrals i, 5, short, coalescent, not adnate to abdomen. Caudal 
large, central rays produced, its length equal to five-sixths of head. Genital papilla in the male 
slender, tapering, longer than first, anal ray and 1.5 times diameter of eye; that in the female half as 
long and twice as broad as in the male. Scales large, strongly ctenoid, 23 or 24 in lengthwise series 
and 6 in transverse series. 
Colors: In life, apparently almost transparent; muzzle black; a black line at base of anal; back 
and head sparsely spotted with black; a narrow black stripe under eye. 
Average length about 12.5 mm., the males somewhat smaller than the females. 
Types (Nos. 50303 and 50304, U. S. National Museum), collected in Lake Buhi, Luzon, Philippine 
Islands, July 5, 1901, by I>r. F. W. Richardson. 
This is apparently the smallest known species of fish. The average length of females among the 
specimens at hand is 13.5 mm., the minimum under 12 mm. The average length of males is 12.5 mm., 
the minimum under 10 mm., and the maximum 13.5 mm. The average length of 50 specimens taken 
at random, both sexes about equally represented, was 12.9 mm. 
That these specimens are mature is shown by the presence of ripe ovarian eggs and by the extru- 
sion of perfect eggs when the fish were placed in the preserving fluid. The average diameter of the 
extruded eggs is 0.5 mm. 
The shape of the genital papillje suggests that the eggs are deposited in crevices or under objects, 
and there fertilized. 
Prof. H. V. Wilson, of the University of North Carolina, has examined this fish with reference to 
its eggs, and communicates the following notes thereon: 
“The ripe ovarian egg is uniformly filled with granular yolk. It is of a rounded shape, frequently 
elliptical in outline. It lies inside a comparatively thick shell, which has an irregularly polyhedral 
shape. Oiie facet of the shell is convex and bears a small, rounded depression, from which radiate 
