390 CALIFORNIA ACADEMY OF SCIENCES. 



Lateral plates hispid and with a marginal series of 

 spines. 



Distance of the dorsal fin from tip of snout little more 

 than 2 in the length; dorsal fin emarginate, its spine 

 as long as the head to the upper angle of gill-opening. 



Spine of the adipose fin small, its distance from the 

 dorsal fin almost twice the length of the latter. 



Caudal deeply emarginate, its lobes pointed, equal in 

 length to the dorsal spine. 



Pectoral spine, in the young, reaching to middle of 

 ventrals, in the old to the origin of the anal, its outer 

 margin with 2 series of spines, largest near the tip. 



Ventrals short, not reaching beyond the vent. 



Light brown, anterior dorsal rays spotted with darker; 

 caudal fin barred with brown. 



Head 2-24; D. I, 7; A. I, 5; V. I, 5; P. I, 6; Lat. 1. 

 22-23. 



Six specimens .06-.09 m. Teffe; Obidos; Manacapuru; 

 Iga; ? E-io Negro. Agassiz, James and Dr. Jeffrys. 



335, Hypoptopoma gulare, 



Hypoptopoma gulare Cope, Proc. Am. Phil. Soc. xvii, 1878, 679 (Mar- 

 anon; Eigenm. & Eigenm. Proc. Cal. Acad. 2d Ser. ii, 40, 1889. 

 Habitat: Maranon. 



336, Hypoptopoma carinatus. 



Hypoptopoma carinatus Steindachner, Denk. Ak. Wien, xli, 49, pi. 



vi, 1879 (Amazon near Peruvian boundary); E. & E. 1. c. 

 Habitat: Solimoens near Peruvian boundary. 



LXXVII. HISONOTUS. 



Hisonotus Eigenm. & Eigenm. Proc. Cal. Acad. 2d 

 Ser. ii, 40, 1889 (notatus). 



Type: Hisonotus notatus E. & E. 



This genus is distinguished by its large ventral plates, 

 superior eyes, unperforated humeral plate, and absence 

 of an adipose fin. 



Habitat: Southeastern Brazil. 



