90 THE CYPRINODONTS. 
median series on the flank as wide as the eye. Intestine short. A female of 
an inch and a quarter contained twenty two embryos. 
Light olivaceous, yellowish to brownish, with seven to ten vertical bars of 
brownish, separated by light or silvery spaces of equal width, on the sides of 
the caudal portion, edges of scales darker, centres of scales in the median 
series on the flank more or less silvery. Belly and lower surface of head 
silvery to golden. The black of the inside walls of the abdomen shows 
rather plainly on the outside. Occiput dark; top of snout light. A dark 
line between anal and caudal. Dorsal with a faint spot or group of puncti- 
culations behind the middle near the base ; other fins plain to dark tipped. 
Isthmus of Panama, fresh waters. 
HETERANDRIA. 
Heterandria Agassiz, 1853, Am. Jour. Sci., XVI, 185,—1854, Am. Jour., XVII, 365,—Tenn. Riv. 
i } 
ca etei (Part) Blk., 1860, Cypr., 481; Gth., 1866, Cat., VI, 851; Jor. & G., 1882, B. 16 U.S. 
Mus., 348. 
Shape of the body similar to that of the Funduli, compressed, rather 
elongate ; somewhat depressed on the head. Snout short, narrow. Chin 
steep. Mouth small, narrow, very protractile; mandibles longer, firmly 
united ; intermaxillaries shorter. Teeth in bands, hooked, outer series 
larger, firmly set, appearing slightly compressed or spear-shaped when seen 
from front or rear. Gill membranes short, united, free from the isthmus. 
Branchiostegal rays commonly five. Dorsal fin smaller and originating back- 
ward of the anal. Anal opposed to dorsal in females, greatly advanced and 
modified into an intromittent organ in the males. Ventrals small, more or 
less modified in males. Scales large. Intestine medium to elongate. 
The species placed in this genus differ from those of Gambusia in the 
shape of the teeth, the structure of the mouth, and in the number of bran- 
chiostegal rays. Heterandria is still farther separated from Girardinus, 
as is seen in the structure of the mouth, the dentition, the length of the 
intestine, ete. 
The Carolinas to the Argentine Republic. 
