1 6 ZOOLOGY OF THE VOYAGE OE H.M.S. SAMAKANG. 



openings, situated before and above tbe level of the eye, the tips of the anterior opening 

 being tumid. The distance between the eyes is nearly half the length of the head, and the 

 mouth is small, with the loose tips granulated or fringed interiorly. The anus is lax, and is 

 full}- a quarter of an inch before the anal fin. 



By dissection, the preoperculum is found to have a broad flat disk with numerous 

 furrows towards its border. Its under limb is one-third longer than the upper one, which is 

 vertical. They meet at a right angle, and the corner is very slightly rounded. The under 

 edge is straight and horizontal, and lies in contact with, and partly conceals, the gill-rays. 

 The body of the operculum is triangular, with a prominent ridge or crest near its articulation, 

 and a narrow, flat process descending from its anterior edge, over a thin plate, formed by the 

 interoperculum and suboperculum, which lie wholly behind the preoperculum, and are closely 

 joined by membrane to one another. The hyoid bone gives attachment to five slender, curved 

 branchiostegous rays, and the point of the uppermost can be felt through the integuments at 

 the margin of the gill-opening, where it projects. Beneath the rays there is a broad thin plate, 

 undulated so as to give lodgment to several large muscles, and articulated to the body of the 

 hyoid bone. It looks like a greatly developed gill-ray, or rather like several (four) confluent 

 rays, being traversed by three lines, indicating the points of union. The anal and dorsal are 

 rather high, and the latter is the narrowest. The two fins terminate opposite to each other, 

 but the dorsal commences a little farther forward. The caudal is even at the end, and the 

 pectoral is much rounded. 



The upper half of the fish is deep black, but there are some scattered round marks on 

 the back of greyish-black, in general not much paler than the groimd colour. In one speci- 

 men, however, these spots look whitish, as if the pigment were partially worn off. The under 

 surface is white, and there are some orange tints on the flanks. The black and white meet 

 in an irregular, clouded manner. The anal is white. The other fins are more or less clouded 

 or mottled with black. Length, 5 J inches. 



Hab. China Sea. 



Of the species named in the Begne Animal, p. 368, as belonging to the division 1° D., 

 T. testudineus, Bl. 139, differs in its colour and markings, as well as in the general diffusion 

 of the spines on the chin, flanks, and tail, as well as on the belly and back. Lacepede would 

 appear to have confounded more than one species under the name of hispidus, as he states it 

 to be an inhabitant both of the embouchure of the Nile, and of the Indian Ocean. His 

 figure is copied from one of Commerson's designs, and is studded on the back with round, 

 well-defined, white dots, in which as well as in the band-like processes of the dark ground 

 colour, which run from the back into the white of the belly, the species differs from atratus. 

 The T. hispidus of Bloch, pi. 142, has similar lateral descending bars of the dark colour without 

 the superior white clots. T. patoca of Buchanan Hamilton, pi. 18. f, 2, differs from atratus in 

 its more arched back, more prominent upper jaw, and in the numerous yellow angular spots on 

 the back. Of the many handsome species figured in the Fauna Japonica by M. Schlegel, 



