100 
BULLETIN OF THE UNITED STATES FISH COMMISSION. 
head, with a broad, shallow, nearly naked median groove, which is wider behind and forks at nape. 
Supraorbital bones with radiating strise. Jaw's unusually short, stiff, strong, rapidly tapering forward; 
large teeth of jaws very strong, knife-shaped. Upper jaw from eye about 1.75 times as long as the 
rest of head. Eye large, 7 in snout, 2.66 in postorbital part of head, and 1.8 in interorbital width. 
Maxillary entirely covered by preorbital. Cheek densely scaled; opercle mostly naked except along 
the anterior margin. Scales of body minute, especially above. Dorsal fin low posteriorly, height of 
its anterior lobe equaling that of anal, or length of postorbital part of head, its longest ray two-fifths 
the base of fin; last rays of dorsal and anal much elevated in young; caudal lunate, its lower lobe 
nearly half longer than upper; middle rays about as long as eye. Yentrals inserted midway between 
base of caudal and middle of eye, their length a little less than that, of pectoral and equal to post- 
orbital part of head; insertion of anal opposite that of dorsal. 
Green, silvery below; no lateral stripe; pectoral and dorsal blackish; scales and bones green. 
This species reaches a length of 3 to 5 feet, and is generally abundant in the West Indies from the 
Florida Keys to Brazil, the young occasionally reaching northward, having been reported by Dr. Bean 
from Ocean City, N. J. It is the most common species of the genus in Porto Rico, having been obtained 
at San Juan, Mayaguez, Ensenada del Boqueron, Isabel Segunda, and Culebra. It is a vigorous fish and 
sometimes dangerous in its leaps from the water. 
Belone raphidoma Ranzani, Nov. Comm. Ac. Nat. Sci. Inst. Bonon., V, 1842, 359, pi. 37, fig. 1, Brazil. 
Belone gerania Cuvier & Valenciennes, Hist. Nat. Poiss., XVIII, 437, 1846, Martinique. 
Belone crassa Poey, Memorias, II, 291, 1861, Cuba; Poey, Fauna Puerto-Riqueiia, 337, 1881; Stahl, 1. c., 79 and 166, 1883. 
Belone melanochira Poey, Memorias, II, 294, 1861, Havana. 
Tylosurus gladius Bean, Proc. U.S.N.M. 1882, 239 and 430, Pensacola. 
Tylosurus raphidoma, Jordan & Evermann, 1. c., 715, 1896. 
Family XXI 1 1. HEMIRAMPHID^E. The Balaos. 
Body elongate, more or less compressed, covered with large cycloid scales; upper jaw short, 
lower jaw various, sometimes much produced, the toothed portion at base fitting against the toothed 
premaxi llaries; teeth equal, mostly small and tricuspid; maxillaries anchylosed to premaxi llaries. 
Gillrakers long. Caudal fin rounded, or forked; if forked, the lower lobe the longer. Anal fin modi- 
fied in the viviparous species (Zenarchopterus) , unmodified in the others and usually similar to 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 cavity of 
the latter; fourth upper pharyngeal wanting or grown fast to third ; lower pharyngeal large, thick, 
triangular, with concave surface. Vertebrse about 50. (Characters verified in Hemiramphus hrowni, 
Hyporamphus roberti, and Chriodorus atherinoides . ) 
Herbivorous fishes of 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. 
a. Lower jaw bluntish, not at all produced; teeth rather large; the pectorals and ventrals moderate; shore 
fishes Chriodorus 
aa. Lower jaw acute, longer than upper, or more or less produced; teeth small; species oviparous, anal fin in the male 
not modified, caudal fin unequally lunate. 
b. Lower jaw produced in a long pointed beak, usually longer than rest of head. 
c. Body moderately compressed; pectoral moderate; shore fishes. 
d. Air-bladder simple; sides of body more or less convex; ventrals inserted anteriorly, far in advance of 
dorsal Hyporhamphus, 34 
dd. Air-bladder cellular; sides of body nearly vertical and parallel; ventrals inserted posteriorly, not far before 
dorsal Hemiramphus, 35 
cc. Body very slender and compressed, more or less band-like; pectoral fins very long, ventral very short, inserted 
posteriorly; pelagic species Euleptorhamphus 
