130 
BULLETIN OF THE UNITED STATES FISH COMMISSION. 
Famil) XLII. EXOCIETI ll.-E. Flying-fishes. 
Bodj^ oblong or elongate, covered with cycloid scales, which are rather deciduous; lateral line 
running very low, along the side of the belly; head more or less scaly with vertical sides; mouth 
moderate, terminal, the jaws not prolonged into a beak; premaxillaries not protractile, hinged at base 
mesially; margin of the upper jaw chiefly formed by the premaxillaries, the short maxillaries enter¬ 
ing the lateral margin; maxillary free from the premaxillary, its edge slipping under the front of the 
preorbital; dentition various, the teeth small and weak; dorsal fin without spines, inserted on the 
posterior part of the body, opposite the anal anil more or less similar to it; ventrals abdominal, of 
several soft rays, inserted posteriorly; pectoral fin inserted high, used as an organ of flight; shoulder- 
girdle and pectoral muscles very strong; caudal fin forked, the lower lobe the longer; no finlets; vent 
close in front of anal; nostrils large, double, near the eye; lower pharyngeals enlarged and fully united, 
forming a large, transversely concave plate, covered with large, close-set, blunt, tricuspid teeth; third 
upper pharyngeal greatly enlarged, not united with its fellow, both covered with large, blunt, tricuspid 
teeth; fourth superior pharyngeal wanting in the adult (probably co-ossified with the third)—these 
characters verified on Exoccetw californicus —vertebra' without zygapophyses; gill-membranes not united, 
free from the isthmus; pseudobranchiae hidden, glandular; gillrakers various; gills 4, a slit behind the 
fourth; air-bladder very large, not cellular so far as known, and extending far backward among the 
hsemopophyses of the caudal vertebrae; vertebrae about 50; intestinal canal simple, without cieca. 
Carnivorous or herbivorous fishes. Genera 6 or 8; species about 65; abounding in all warm seas, mostly 
pelagic, swimming near the surface, and skipping or sailing through the air, sometimes for consider¬ 
able distances. 
a. Pectoral fins moderate, not reaching beyond middle of dorsal fin; dorsal more or less elevated; anal long, its base 
scarcely shorter than dorsal. 
/>. Pectoral not reaching the ventrals. Evolantia, p. 130 
bb. Pectoral reaching beyond ventrals to dorsal or for the first third of its length .... Pprcxoccetus, p. 131 
aa. Pectoral fins very long, their tips usually reaching to base of caudal; lower jaw little prominent, snout short, 
c. Ventral fins inserted anteriorly, much nearer tip of snout than base of caudal, not used as organs of flight, their 
tips not reaching nearly to front of dorsal; anal fin long, its base nearly equal to that of dorsal. .Exoccctus p. 132 
re. Ventral fins inserted posteriorly, more or less near base of caudal than tip of snout, used as organs of flight, and 
their tips reaching past middle of base of anal. 
d. Anal fin long, equal to dorsal fin. Exonautes, p. 133 
del. Anal fin short, not equal to dorsal fin. Cypsilurns, p. 131 
Genus 75. EVOLANTIA Snodgrass &. Heller. 
This genus differs from other genera of flying-fishes chiefly in the short pectoral, which does not 
reach the ventrals; no teeth on roof of mouth; ventrals small, midway between pectorals and base of 
caudal. 
Evolantia Snodgrass & Heller, Fishes of the Galapagos Islands, in Proc. Wash. Ac. Sei., V, 1903 (Sept. 12), 1S9 ( microptera ). 
88. Evolantia microptera (Cuvier & Valenciennes). “ .Unlolo." Fig. 44. 
Head 4.25 in length; depth 6; D. 13; A. 15; P. 12; V. 6; scales to base of caudal about 45; about 
10 scales in a transverse series to middle of belly; width of head less than its depth and about 2 in 
its length; snout 4 in head, eye 3.5, 1.5 in postocular part of head, I in interorbital space; ventral 2.3 
in head; base of dorsal 1.3; pectoral 2.75 in body. 
Body elongate, compressed; head elongate, pointed in front, the upper profile more or less convex; 
snout rather short, pointed, and rounded; eve anterior, well behind center of length of head, and the 
bony rim behind slightly keeled out ward; mouth small, superior, the mandible projecting well beyond 
the snout; teeth in jaws minute, none on roof of mouth; tongue rounded, and free around the edges; 
nasal cavity moderately small, above eye in front, and with a thick, fleshy flap; interorbital space 
broad, very slightly concave; gillrakers slender, pointed, rather numerous, and much shorter than the 
long gill-filaments; peritoneum brown; scales cycloid; lateral line running along the lower part of 
side; origin of dorsal apparently nearer tip of caudal (damaged) than base of pectoral, and well in 
advance of the anal; dorsal high, the median ridge elevated; anal high, the anterior rays elevated ; 
caudal deeply forked, the lower lobe the longer; pectoral moderately long, not reaching the origin of 
