42. IIOl'LABELUS. 103 



forked ; the upper lobe is soiucwliut tlie 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 

 mueosus. 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 the 

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

 lower parts silvery, with a reddish tinge. 



Guatemala. 

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

 From Mr. Salvin's Collection. 



12. Amiurus furcatus. 



Pimelodus furcatus, Cia: ^ Vol. xv. p. 136 (not P. cauda-fnrcatm, 

 Lesuem-). 



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

 Head one-fom-th longer than broad ; the maxiUary barbels do not 

 extend 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, 

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



nelodus affinis, Bdirrl^- Gi'rard, in Pruc. Acad. Nat. Sc. Phi/ad. 1854, 

 3. -26, and Icht/i. U. S. ^- Mex. Bound, p. 32. pis. 1(3 & 17. 



13. Amiurus aflBnis. 



Pimelodus 

 P- 



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

 The length of the head is two-ninths of the total (^^•ithout caudal), 

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

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

 torals. 



Texas, 

 rt. HaK-grown. Presented by the Smithsonian Institution. 



42. HOPLADELUS. 



Leptops, Opladelus, Ilictis, Pylodictis, etc., Ra/iiicsqtte, Ichth. Ohiens. 



pp. 04-67. 

 Hopladelus, Gill, Proc. Post. Soc. Xat. 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 

 cmarginate ; ventral rays nine. Branchiostegals twelve. 



Xorth America. 



