126 
BULLETIN OF THE UNITED STATES FISH COMMISSION. 
This fish was common in the Honolulu market, where it is regarded as a good food-fish. We have 
thus far failed to find any difference between the Pacific species and the common Athlenneshians of the 
West Indies. 
Bclonc Mans Cuvier & Valenciennes, Hist. Nat. Poiss., XVIII, 432, 1846, Havana, -Bahia ; Gunther, Cat., vi, 1866, 248 (copied) ; 
Steiudachner, Ichth. Beitr., Ill, 64, 1875 (Acapulco). 
Tylosurus Mans , Jordan & Gilbert, Synopsis, 373, 901, 1883. 
Atlilennes Mans , Jordan & Evermann, Fish. North & Mid. Amer., I, 718, 1896; Jenkins, Bull. U. 8. Fish Comm., XXII, 1902 
(Sept. 23, 1903), 433 (Honolulu); Snyder, op.cit. (Jan. 19, 1904), 521 (Lahaina, Maui). 
Family XLI. HEM I RAM PH I Dik. — The Balaos. 
Body elongate, more or less compressed, covered with large cycloid scales; upper jaw short, low'er 
jaw variable, sometimes much produced, the toothed portion at base fitting against the toothed pre- 
maxillaries; teeth equal, mostly small and tricuspid; maxillaries ankylosed to premaxillaries; gill- 
rakers long; caudal fin rounded or forked; if forked, the lower lobe the longer; anal fin modified in 
the viviparous species (Zenarchopterus) , unmodified in the others and usually similar to the dorsal; no 
finlets; air-bladder large, sometimes cellular; third upper pharyngeal on each side much enlarged, 
solidly united with its fellow to form an oval plate, with slightly convex surface and covered with 
blunt tricuspid teeth; this is about as large as the united lower pharyngeals and fits into the con- 
cavity of the latter; fourth upper pharyngeal wanting or grown fast to the third; lower pharyngeal 
large, thick, triangular, with coneave surface; vertebrae about 50. Probably not separable from the 
Exoccetidse. 
Herbivorous fishes of the warm seas; mostly shore species, a few pelagic. They feed chiefly on 
green algae, and, like the related forms, swim at the surface, occasionally leaping into the air. Size 
rather small, about a foot in length. Genera about 7; species about 75. 
a. Body moderately compressed; pectoral moderate. Shore fishes. 
b. Ventrals inserted anteriorly, far in advance of dorsal; air-bladder simple; sides of body more 
or less con vex Hyporhamphus, p. 126 
bb. Ventrals inserted posteriorly, not far before dorsal; air-bladder cellular; sides of body nearly 
vertical and parallel Hemiramphus, p. 127 
aa. Body very slender and compressed, more or less band-like; pectoral fin very long, ventral very 
short, inserted posteriorly. Pelagic species Euleptorhamphus , p. 128 
* 
Genus 72. HYPORHAMPHUS Gill. The Halfbeaks. 
Body elongate, moderately compressed, the sides of body not vertical, but more or less convex, 
the dorsal outline parallel with that of the belly. Upper jaw short; lower jaw prolonged into a slender 
beak, bordered with membrane, this beak shorter in the young; premaxillaries forming a triangular 
plate, the teeth of which fit against the toothed portion of the mandible; maxillaries joined to premax- 
illaries; teeth feeble, mostly tricuspid; gillrakers rather long; head covered with large shield like 
scales; scales deciduous; caudal fin more or less forked, the lower lobe the longer; no finlets; dorsal 
and anal similar, opposite each other, not modified in the males; last ray of dorsal usually short; ven- 
trals small, inserted well forward, nearly midway between opercle and base of caudal. Air-bladder 
large, simple, not cellular. Young with the lower jaw short. Sides in our species with a distinct 
silvery band, as in Atlierina. Oviparous. Species numerous in all warm seas, going in large schools, but 
usually remaining near shore, feeding chiefly on green algse. Size comparatively small. 
One species known from Hawaiian waters. 
Hyporhamplius Gill, Proc. Ac. Nat. Sci. Phila. 1859, 131 ( tricuspidatus = unifasciatus). 
85. Hyporhamphus pacificus (Steindachner). Fig. 41. 
Head (from tip of snout) 4.6 in trunk; depth 9.5 in trunk; D. 15; A. 18; P. 12; Y. 6; scales about 
64 in a lateral series; width of head about 1.5 in its depth; snout 2.67 in head; eye 4.25, 1.5 in 
postocular part of head, about 1.67 in snout, and 1 in interorbital space; pectoral 1.5 in head; 
ventral 2.67. 
Body moderately elongate, compressed, the back rounded rather broadly; head flattened above, 
the sides compressed, and the lower surface narrowly constricted; snout a trifle over 4 in space 
