TETR AODONTID.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. 



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



spine BALISTES, 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. 



MONACANTHUS, 241. 



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



ALUTERA, 242. 



240. BALISTES (Artedi) Linnaeus. (/3aX, 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. (Balisles.) 



478. B. carolinensis Gmelin. LEATHER-JACKET. TRIGGER- 

 FISH. Soft D. high; C. lobes elongate in adult. Brownish; young 

 spotted with darker; 2d D. and A. with interrupted brown streaks ; 

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

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

 seas, rarely N. to Cape Cod. (En.) 



241. MONACANTHUS Cuvier. (fiovos, one ; atavQa, spine.) 



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

 dorsal spine with retrorse barbs. 



479. M. hispidus (L.). FOOL-FISH. FILE-FISH. No recurved 

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

 greenish, mottled with darker. Head 3f ; depth If. D. 1-32. 

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



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



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

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

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

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

 the Revolutionary War, and an excellent naturalist.) 



FAMILY XCI. TBTBAODONTID^E. (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 



