342 CALIFORNIA ACADEMY OF SCIENCES. 



A single specimen .065 m. " Maraiion & Ucayale " 

 Chas. Sarkaday. 



LXIV. Stegophilus. 



Stegophiliis Reinhardt, Naturhst. Foren. Meddel. 1858, 

 79, pi. ii (insidiosiis). 



Type: Stegophilus insidiosus Reinhardt. 



Body elongate, slender, head depressed, the mouth in- 

 ferior, each jaw with fine teeth arranged in regular 

 series; no teeth on the vomer; upper lip with two or 

 more series of elongate freely movable teeth. Orbit 

 without a free margin; gill-membrane joined to the isth- 

 mus, the gill-opening a narrow slit in front of the pec- 

 torals; opercle and preopercle with a bunch of strong 

 spines. Dorsal and anal placed posteriorly; ventrals in 

 front of the dorsal. 



Habitat: Rio Plata; Rio das A'elhas; Amazon and its 

 tributaries. 



Reinhardt states that S. insidiosus lives in the gill- 

 cavity of Sorubim. He seems to have taken the labial 

 teeth for intermaxillary teeth, and the intermaxillaries 

 as the branches of the vomer. 



ANALYSIS OF THE SPECIES OF STEGOPHILUS. 



a. Caudal emargiuate. 



b. Back spotted, sides with a series of dark spots. D. 8-9; A. 7. 

 c. Dorsal 8; head as long as broad. 



d. Origin of dorsal nearer tip of snout than tip of caudal; head 8 in 



the total length; eye 3h in the head; lateral spots most jironiinent 



on the tail; tips of the caudal lobes duskj'; base of caudal with a 



double spot. (Steindachner.) maculatun 278. 



dd. Origin of dorsal much nearer tip of caiidal than tip of snout; 



head 6^ in the total length, eye 4 in the length; lateral spots most 



prominent under the dorsal; caudal with a dark bar extending 



from the tips of the lower rays to the middle of the upper; base 



of caudal with dark spots. (Boi;lenger.) punciatus 279. 



cc. Dorsal 9; head longer than broad, 6i in the total length; eye 3i in 



the head; origin of dorsal much nearer tip of caiidal than tip of 



snout; lateral spots most prominent on the tail; caudal with faint 



dusky spots. intermcdius 280. 



