376 CALIFORNIA ACADEMY OF SCIENCES. 



This species is closely related to Loricaria viaculata 

 Bloch and to L. spixii Steindachner, but is readily dis- 

 tinguished by the large, angular, orbital notch, by the 

 broad, black margined lower lip, by the teeth and by the 

 anal plate. 



Depth about 1| in the width. Head long, narrow, de- 

 pressed, its depth lf-2 in its width; postorbital region 

 flattish, the occipital with two distinct keels in the young, 

 which become more or less obsolete in the old; the occip- 

 ital ends in an attenuated process which is margined by 

 three nuchal plates; interorbital concave, the superciliary 

 inargins being slightly raised. Snout long, pointed; a 

 narrow naked strip at its tip. 



Orbit with a large, angular, rhomboidal notch, the 

 diameter, including the notch, 4 in the head; diameter 

 of the eye 3J in the snout, Ih in the head, 1 in the space 

 between the orbital notches. Lower surface of the head 

 naked, the lower lip greatly expanded, entirely covering 

 the naked portion. Teeth small, numerous, well devel- 

 oped. 



A large, elongate anal plate, broadly rounded in front, 

 margined by three large plates, together forming a large 

 ventral buckler. Bell}^ with three series of plates; breast 

 with numerous smaller plates. Nuchal plates bicarinate; 

 lateral keels strong, remaining distinct, approximated 

 on about the nineteenth lateral scute. Surface of the 

 anterior scutes and of the head with longitudinal series 

 of small spines. 



Distance of dorsal fin from tip of snout 2f-3 in the 

 length, first dorsal ray about as high as the length of the 

 head. Caudal emarginate. Anal fin large, its first ray 

 little lower than the dorsal. Ventrals lower than the 

 anal, reaching to or little beyond origin of the anal lin. 

 Pectorals less than the ventrals, about reaching the 

 latter. 



