134 PROOEEDINGS OF THE ACADEMY OF 



fin. Orbit one-third length of head (to gill opening), and nearly 

 equal interorbital width. Mandibular barbel to end of postcora- 

 coid process ; maxillary to end of pectoral spine. Width of 

 casque greater than the interorbital. Radii D. L. 6 ; A. 12 ; V. 

 1 ; P. I. 4. Dorsal spine grooved, not dentate ; pectoral spine 

 strongly toothed extending be^'ond basis of ventral fin. Post- 

 clavicle with recurved teeth ; caudal fin truncate. Lateral shields 

 26 low, leaving a broad naked band above and below them ; with 

 a single strong median curved spine. Color brown above, with 

 a j-ellow band along the middle of the side border red with black 

 above and below. Belly white ; below the pectoral fin purple. 

 Caudal fin with some vertical dark bars. Total length, .082 ; do. 

 to first anal ray, .045 ; do. to end of postcoracoid, .026 ; do. to 

 base of dorsal fin, .026 ; do. to gill opening, .016 ; do. to orbit, .004. 

 From Nauta. The less exposure of the scapular arch below, 

 simple postcoracoid, etc., distinguish this fish from the Z. moni- 

 tor^ m. According to the description of Dr. Giinther the Boras 

 asterifrons pertains to the genus Zathorax. 



RMnodoras niger, Valenciennes ; Gthv. v. 209. 

 Nauta. 

 One of the specimens is twenty-five inches in length. 



Rhinodoras prianomus, sp. nov. 



Head long, extending (measured to the end of the opercular 

 flap) the length of the short body to the origin of the npper and 

 lower caudal radii, 2.5 times. The eye is one-seventh the length 

 of the head, and is equidistant between the end of the muzzle and 

 the edge of the operculum, and is half the interorbital width. 

 Lateral scuta 22 ; the first and last with rudimental spine ; that 

 of the others strong and curved, the upper edge of the scutum 

 with two or three prickles. The scuta leave a wide naked space 

 above and below them. Radii, D. I. 6; A. 10; V. 7; P. I. 10. 

 Dorsal and pectoral spines serrate to the base on their anterior 

 edges; postclavicle with a longitudinal angle, which supports a 

 series of processes and spines. Head and casque rugose above. 

 Maxillary barbels reach to bej^ond eye ; the outer mentals are 

 .66 as long. Color brown, paler below, with numerous vertical 

 dark brown spots on the sides. All the rayed fins, and the back 

 at the base of the adipose, black. Head above and at sides gray 



