SOUTPI AMERICAN NEMATOGNATHI. 451 



depressed, margined with bristles in front of the pre- 

 opercle. Caudal forked. 



443, Scleromystax barbatus, 



Callichthys barbatus Quoy & Gaimard, "Voy. Uran. Zool. 234;" 

 Cuv. & Val. Hist. Nat. Poiss, xv, 322, 1840 (Kio Janeiro); Giin- 

 ther, Cat. Fish. Brit. Mus. v, 229, 1864 (copied). 



Scleromystax barbatus Eigenm. & Eigenm. Proc. Cal. Acad. 2d Ser. 

 i, 164, 1888 (name only). 



Habitat: Rio Janeiro. 



Mouth very small, protractile; maxillary barbels reach- 

 ing to the middle of the opercle; Sazygous shields before 

 the adipose fin. 



Dorsal and anal with blackish spots. D. I, 6; A. 7; 

 Lat. plates f|. (Quoy & Gaimard.) 



XCVI. CALLICHTHYS. 



Callichthys Linnaeus, Amoen. Acad. i, 317, 1754. 



Callichthys Cuv. & Val. Hist. Nat. Poiss. xv, 294, 1840 

 (<isj>er= callichthys). 



Callichthys Bleeker, Nederl. Tijdschr. Dierk. i, 82, 1863 

 (tamoatacallichthys). 



Cat(ij>hr<(ctu,8 Bloch, Ausl. Fische, viii, 80, 1794 (pre- 

 occupied in Mammals). 



Cataphractus Lacepede, Hist. Nat. Poiss. v, 124 (call- 

 ichthys). 



Cataphractus Swainson, Fishes, Reptiles, etc., ii, 304, 

 1839 (depressus=callichthys). 



Type: Silurus callichthys Linnaeus. 



Habitat: La Plata to Trinidad. 



ANALYSIS OF THE SPECIES OF CALLICHTHYS. 



a. Lateral plates flf; barbels reaching beyond the gill-opening. 



callichthys 444. 



aa. Lateral plates ff; inner barbel reaching to the eye, the outer one 

 shorter; a series of small spines in front of the adipose fin; light brown, 

 with small darker spots. D. 9; A. 7. (Hensel.) arcifer 445. 



