42. HOPLADELUS. 103 



forked ; the upper lobe is somewhat the longer, its length being 

 equal to, or a little less than, that of the head. The anal fin termi- 

 nates behind the adipose fin, and its last rays do not extend to the 

 base of the caudal. Axil of the pectoral with a very distinct porus 

 mucosus. The pectoral spine is serrated interiorly, sometimes a little 

 longer, sometimes a little shorter, but always rather stronger than 

 that of the dorsal fin. Pectoral fin longer than ventral, two-thirds 

 or three-fifths of the length of the head. The ventral extends to t; ? 

 origin of the anal. Upper parts brownish, with steel-blue reflexions ; 

 lower parts silvery, with a reddish tinge. 

 Guatemala. 



a-c. Adult (15 inches long) and half-grown. Rio Usumacinta. 

 From Mr. Salvin's Collection. 



12. Amiurus furcatus. 



Pimelodus furcatus, Cuv. fy Veil. xv. p. 136 (not P. cauda-furcatus. 

 Lesueur). 



B. 8. D. 1/6. A. 32-34. P. 1/10. 

 Head one-fourth longer than broad ; the maxillary barbels do not 

 axtend to the end of the head. Dorsal spine long, rather slender, 

 three-fourths of the length of the head ; pectoral spine shorter, but 

 stronger, than that of the dorsal fin, denticulated interiorly. Adi- 

 pose fin short ; caudal deeply forked. 

 Mississippi. 



«. Half-grown : skin. Mississippi. From Dr. Parnell's Collection. 



13. Amiurus affinis. 



Pimelodus affinis, Bairdfy Girard, in Proc. Acad. Nat. Sc. Philad. 1854, 

 p. 26, and Ichih. U. S. Sf Mex. Bound, p. 32. pis. 16 & 17. 



D. 1/6. A. 35. P. 1/10. 



The length of the head is two-ninths of the total (without caudal), 

 the length of the anal one-third. Adipose fin short ; caudal deeply 

 forked. The maxillary barbels extend beyond the base of the pec- 

 torals. 



Texas. 

 a. Half-grown. Presented by the Smithsonian Institution 



42. HOPLADELUS. 



Leptops, Opladelus, Ilictis, Pylodictis, etc., Rafinesque, Ichth. Ohiens. 



pp. 64-67. 

 Hopladelus, Gill, Proc. Bost. Soc. Nat. Hist. 1862, p. 51. 



Adipose fin short and thick ; dorsal fin short, with a spine con- 

 cealed in the skin and with six rays ; anal fin of moderate length ; 

 barbels eight ; the lower jaw is the longer. Palate edentulous. 

 Head depressed, oblong, covered with thick skin. Caudal fin slightly 

 emarginate; ventral rays nine. B ran chiostegals twelve. 



North America. 



