272 PISCES. 



Cephalus, Sh.' Orthagoriscus, Schn. 



Jaws undivided as in Diodon; but the body, compressed and spine- 

 less, is not susceptible of inflation, and the tail is so short and high 

 that this fish resembles one whose posterior portion has been trun- 

 cated, producing a singular appearance, that is amply sufficient to 

 distinguish it. The dorsal and anal, both high and pointed, are 

 united to the caudal^ the natatory bladder is wanting; the stomach 

 is small and penetrated directly by the ductus choledocus. A thick 

 layer of a gelatinous substance is spread under the skin. 



C. brevis, Sh.; Tetr. mola, L.; Bl., 128.(1) (The Short Sun 

 Fish.) Four feet and more in length, and weighing upwards of 

 three hundred pounds; the skin is very rough, and of a fine sil- 

 ver colour. European seas. 



C. oblongus; Orthagoriscus oblongus, Bl., Schn., 97. (The 

 Oblong Sun Fish.) Skin hard, and divided into small angular 

 compartments. Cape of Good Hope. 



C. spinosus: Orth. spinosus, Bl. Schn.; Diodon mola, Pall., 

 Spic. Zool., VIII, pi. iv, f. ; and better, Kselr., Nov. Com. Pe- 

 trop. X, pi. viii, f. 3. A third and very small species, with a 

 few spines, that is sometimes taken in the Atlantic. 



3d. The flanks only smooth, and with lateral tentacula: T. Spengleri, Bl., 144, 

 Seb., Ill, xxiii, 7 and 8, the same as the Tetr. Plumieri, given from Plumler, La- 

 cep., I, XX, 3. N.B. That what Lacepede considered a lump is only the pectoral 

 of the other side, the point of which is visible, and that the Sphero'ide tubercule, 

 Lacep., II, 1, is drawn from. the same plate of Plumier, and represents the same 

 fisli seen in front. Schneider was aware of this, Bl., Schn., Ind. pi. vii. T. hon- 

 kenii, Bl., 143. 



4tli. Smooth flanks, without lateral tubercles: T. ocellafus, Bl., 145; 7*. furgi- 

 dus, Mitch., pi. vi, f 5; T. lunaris, Russel, 1, 29. 



II. Species with an oblong' head. 



1st. The flanks only smooth: T. arg-e?2iais, Lacep., Ann. Mus. IV, xiii. 

 2d. Back and flanks smooth, the belly only rough: T. lagocephalus, Bl, 143, 

 and Seb. Ill, xxiii, 5 and 6; T. Ixvigatus, Will., pi. J. 2. 



III. With a carinated back. T. rostratus, BL, 146, 2, to which the T. ekdricus. 

 Paters. Phil. Tran's., vol. 76, pi- 3, is closely allied; T. Gronovii. 



(1) Add Ort. oblongus, Schn., 97;Ort. varius, Lacep., I, xxii, 2;0rt. hispi- 

 dus, Nov. Com., Petr., X, viii, 2 and 3. 



N.B. The Ovoidefasce, Lacep., I, xxiv, 2, the Ovum Commersoni, Schn., 108, was 

 described and figured by Commerson from a stufi'ed specimen which he himself 

 suspected was a mutiltited Tetraodon, and which, in fact, is a Tetraodon lineatus 

 that had lost its fins. 



The Sphero'ide tubercuU was given, as we have stated, from a drav^ing of Plumier, 

 which represents a front view of a Tetraodon v/hose vertical fins are not visible. 

 Conf , Schn., index, LVII. These two genera must consequently be suppressed. 



