Jordan and Evermann Fishes of North America. 1743 



aaa. Dermal ossifications all or nearly all 3-rooted, each with a short, stiff, immovable 

 spine. Nasal tentacle simple, with 2 openings. CHILOMYCTERUS, 684. 



aaaa. Dermal ossifications of fiattisb, papery or cartilaginous plates with minute hair- 

 like papillae ; nostril short, entire, with 2 lateral openings. 



LYOSPH^ERA, 685. 



682. TRICHODIODON, Bleeker. 



Trichodiodon, BLEEKER, Atlas Ichth., Gymnodontes, 49, 1867 (pilosus). 

 I Trwhocyclus, GUNTHER, Cat., Yin, 316, 1870 (erinaceus = pilosus) . 



Body oblong, little depressed ; nasal tentacle present ; dermal ossifica- 

 tions very small, each with a pair of lateral roots, and each terminating 

 in a fine, flexible, bristle-like spine; fins as in Diodon, of which the species 

 are possibly the very young. (Qpi%, hair; Diodon.) 



2161. TRICHODIODON PILOSUS (Mitchill). 



This species, which may be simply the very young of Diodon hystrix, is 

 known only from accounts given by Mitchill, Cuvier, and Glinther. It is 

 possible that these 3 descriptions refer to 3 different species, but more 

 likely all of them are based on young Diodons. Mitchill says: " Hairy 

 Diodon (Diodon pilosus). With a covering of bristly hair. Length about 

 an inch and a half ; breadth less than half an inch ; depth nearly a quarter; 

 making a blunt lump of a fish. Is covered all over back, sides, head, 

 and belly with bristly hair. The bristles strong and flexible, without 

 the power to scratch or to prick. Hair about an eighth of an inch in 

 length. Complexion dun or brown, with spots on the back, sides, and 

 toward the belly. Has, at first glimpse, the appearance of a young mouse. 

 Mouth small, midway, and horizontal. Eyes vertical, lateral, and large. 

 No ventral fins. Pectorals broad. Dorsal and anal very far back, and no 

 hair between them and the tail. This is but a small projection from the 

 thick and clumsy body, and is terminated by a fin of 7 rays. Dorsal, anal, 

 and pectoral fins contain each about 13 rays." 



Cuvier, referring to MitchilFs description, says: "We possess in the 

 museum a large individual, more than 2-J- feet long, entirely covered and 

 roughened by slender spines like the points of pins, 1 line of spines prom- 

 inent nearly on the back and on the sides, and 2 or 3 under the belly. The 

 region of the mouth, that of the eyes, the base of each fin, and the end 

 of the tail alone are deprived of spines. The color of the skin is gray, 

 with round brown points scattered all over it 4 or 5 lines broad. Similar 

 spots are scattered on the fins, which seem to have been yellowish in 

 color. While waiting to know if this Diodon is not the adult of that 

 which Mr. Mitchill has described, I will name it Diodon asper." 



Under the name of Trichocyclus erinaceus Gunther describes a very young 

 example, apparently of this same type, as follows: " Jaws without me- 

 dian suture. Body covered with very small dermal ossifications, each 

 with a pair of lateral roots, and a fine, flexible spine. A nasal tentacle. 

 Dorsal and anal fins as in the allied genera. The spines are hair-like, i of 

 an inch long in an example 1 inches long." Locality unknown. 



