TETK AODOXTID.E. — XCI. 169 



openings small, slit-like. Dorsals separate, the first of 1 to 3 

 spines ; 2d D. and A. long ; V. wanting ; pubic bone long, movable, 

 with sometimes a spine at its end. Genera 8; species 100; car- 

 nivorous fishes of the warm seas. 



o. Dorsal spines 3; bocty covered with thick, firm scales; pelvis with a blunt 



spine Balistks, 240. 



aa. Dorsal spine single, or followed by a rudiment; skin with minute rough 

 shagreen-like scales. 

 b. Pubic spine present; gill-slit short, nearly vertical. A. 25 to 35. 



MoXACANTHUS, 241. 



bb. Pubic spine wanting ; gill-slit long, oblique. A. 36 to 50. 



Alutera, 242. 



240. BALISTES (Artedi) Linnaeus. (/3aXw, to shoot; from the 

 trigger-like 2d spine of D.) 



a. A groove before eye; larger plates behind gill opening; teeth white; no 

 spines on tail. (Balistes.) 



478. B. carolinensis Gmelin. Leather-jacket. Trigger- 

 fish. Soft I), bigh; C. lobes elongate in adult. Brownish; young 

 spotted with darker; 2d I), and A. with interrupted l>mwn streaks; 

 C. mottled ; scales on head similar to those on body. Head 3 ; 

 depth If D. 111-27. A. 25. Lat. 1. 51 to 62. L." 18. Warm 

 seas, rarely X. to Cape Cod. (Eu.) 



241 MONACANTHUS Cuvier. (/ioW, one ; a<av8a, spine.) 



a. Pubic spine movable ; ventral flap moderate, not extending beyond it ; 

 dorsal spine with retrorse barbs. 



479. M. hispidus (L.). Fool-fish. File-fisii. No recurved 

 spines on tail ; first soft ray of D. sometimes filamentous. Dull 

 greenish, mottled with darker. Head 3| ; depth 1 J. D. 1-32. 

 A. 32. L. 6. Cape Cod to Cuba, common. (Lat., rough.) 



242. ALUTERA Cuvier. (? ZKovtos, unwashed.) 



480. A. schcepfi (Walbaum). Dull-greenish, marbled with 

 darker; D. spine slender, not barbed ; C. long in young, shorter 

 with age. Head 3f; depth 2\. D. I, 36. A. 38. L. 18. Cape 

 Cod to Texas. (To Johann David Schopf, a Hessian surgeon in 

 the Revolutionary War, and an excellent naturalist.) 



Family XCI. TETRAODONTID^. (The Swell-fishes.) 



Body oblong, little compressed, the skin naked and usually 

 prickly; stomach capable of great inflation; teeth in each jaw con- 

 fluent into two, which form a sort of beak; no fin spines; D. oppo- 

 site A. ; C. distinct ; V. wanting ; P. short ; pelvic bone moderate. 

 Gill openings small; air-bladder present. Genera 7; species 70, in 

 warm seas. They are noted for their power of swallowing air, by 



