150 CALIFORNIA ACADEMY OF SCIENCES. 



108, Pimelodella cristatus. 



JPimelodus insignis Schomburgk, Fish. Brit. Guiana, 180 (not plate). 



Pimelodus cristatus Miiller & Troschel, Schomburgk, British Gui- 

 ana, 628, 1848 (Takutu and Mahu Kivers); Miiller & Troschel, 

 Horn Ichthyol. iii, 4, 1849 (Guiana in Essequibo); Giinther, 

 Cat. Fish. Brit. Mus. v. 117, 1864 (Guiana; Essequibo; Kiver 

 Capin, Para); Vaillant, Bull. Soc. Philom. Series 7, iv, 152, 

 1880 (Calderon); Steindacher, Flussfische Siidamerikas, iv, 4, 

 1882 (Kio Huallaga). 



Pimelodella cristatus Eigenm & Eigenm, Proc. Cal. Acad., 2d. Ser. 

 i, 132, 1888 (San Goncallo; Avary; Villa Bella; Jutahy; Tapajos; 

 Kio Mucuri; Tabatinga; Hyavary; Coary). 



Pimelodus agassizii Steindachner, SB.Ak. Wien, Ixxiv, July, 1876, 

 Ichthyol. Beitr. v, 99 (Peruvian Amazon; Hyavary) 



Pimelodus ophthalmicus Cope, Proc. Am. Philos. Soc. xvii, 675, 1878 

 (Upper Amazon). 



Habitat: Kivers emptying into the Atlantic north of Cape San 

 Roque; whole course of the Amazon. 



The Pimelodus cristatus M. & Tr. and Pimelodus insig- 

 nis Sch. are evidently identical. 



The description of insignis does not agree with the 

 plate which represents Callophysus lateralis Gill=macrop- 

 terus Lichtenstein. 



Schomburgk, 1. c., says that "The Wapisiana Indians 

 call this fish ' Konnairu,' it grows to about the length of 

 eighteen inches. " 



Miiller & Troschel quoting Schomburgk's notes say the 

 " Wapisianas call it ' Komairu; ' it reaches a length of 

 16-18 inches. " 



The statement that insignis has 10 ventral rays may 

 be true, in which case it is of course distinct from crista- 

 tus; but such statements, never verified by any ichthy- 

 ologist, are to be distrusted. 



Pimelodus agassizii does not differ from cristatus. 



The characters assigned to P. ophthalmicus are also 

 present in one or another of the specimens examined. 

 We have found the anal rays to vary from 12-15, and 

 the dorsal in some is very much higher than in others. 



The specimens in the museum are from San Gongallo; 



