346 FISHES OF NORTH CAROLINA. 



298. LAOTOPHRYS TRIQUETER (Linnaeus). 



Trunk-fish. 



Ostracion triqueter Linnaeus, Systema Naturae, ed. x, 330, 1758; India. 

 Lactophrys triqueter, Jordan & Evermann, 1898, 1722, pi. ccbd, fig. 638. 



Diagnosis. — Form ovate, back evenly arched, depth .5 length; sides making an angle of 

 about 30 degrees at back; ventral surface convex; depth of caudal peduncle greater than diam- 

 eter of eye; head .25 length; profile concave; eye about .33 length of head and .8 length of gill- 

 slit; shell without spines, continuous behind dorsal fin; 9 plates along median line posterior 

 to eye; dorsal rays 10; anal rays 10; caudal fin rounded. Color: dark brown above, lighter on 

 belly; each scale except on ventral surface with 1 or more round whitish spots somewhat smaller 

 than pupil; lips, bases of fins, and tip of caudal dark brown or blackish; caudal peduncle marked 

 like sides; caudal margin black, other fins plain; young light green, with numerous round dark 

 greenish blue spots on sides and below, {triqueter, three-angled.) 



The occurrence of this trunk-fish on the United States coast north of Florida 

 does not appear to have been previously noted. There are 3 North Carolina 

 records. In July, 1900, several young examples were taken in Beaufort Harbor, 

 and in July, 1904, a number of others were obtained in the same locality. The 

 only adult specimen was collected at Perry Island, Beaufort Harbor, in the 

 summer of 1902. 



Family TETRAODONTID^. The Swell-fishes. 



The fishes of this family have the faculty of inflating themselves with air or 

 water, which is pumped into a special sac, lying external to the peritoneal cavity, 

 its duct^opening into the mouth or esophagus. The amount of the inflation is 

 extreme in some genera, the fishes being converted into veritable balloons. 

 Body oblong or elongate, little if at all compressed; mouth small, terminal, the 

 teeth in each jaw fused into a kind of beak with a median suture; lips conspic- 

 uous; gill-slits small, situated immediately in front of pectorals; scales absent, 

 the skin usually covered with small, weak, movable prickles or spines; lateral 

 line conspicuous or not; air-bladder present; vertebrae few (16 to 21); spinous 

 dorsal and ventral fins absent; dorsal fin placed near the caudal, composed of a 

 few soft rays; anal fin similar to and opposite dorsal; caudal fin well developed, 

 of various shapes; pectoral fins short and broad, the upper rays longest. These 

 fishes are for the most part found in warmer coastal waters, and have only feeble 

 swimming powers. While some of them attain a considerable size, none are 

 food fishes, the flesh being rank and sometimes poisonous. About 10 genera and 

 60 species; 4 genera American, 2 represented in North CaroUna fauna. 



i. Body oblong; skm prickly or with soft appendages above and below, sometimes smooth; 



dorsal and anal fins short, with 6 to 8 rays; caudal more or less roimded; lower surface of 



body without a prominent longitudinal fold or keel; size moderate or small. . . . Spheroides. 



a. Body elongate; skin of abdomen very prickly, back and sides smooth; dorsal and anal fins 



falcate, with 12 to 15 rays; caudal fin strongly concave behind; a prominent longitudinal 



fold or keel on each side of belly and peduncle; size large Lagocephalus. 



Genus SPHEROIDES Dum€ril. Puffers; Swell-fishes. 

 Typical puffers, with oblong, plump body; short nasal canal on each side, 

 with 2 openings near its tip; skin either smooth, prickly, or with cirri (prickly 



