424 ME. a. A. BOULENGEE ON FISHES 



opercular cleft ; mandibular barbels short. Gill-cleft extending to below centre of eye. 

 Humeral process striated, twice as broad and half as long as pectoral spine, obliquely 

 truncated posteriorly. Pectoral spine longer than dorsal, a little longer than head, 

 strongly serrated on both sides. Dorsal I 5 ; spine rather feebly serrated on both 

 sides, a little shorter than the head, a little nearer the adipose fin than the end of the 

 snout. Adipose fin not half as long as anal. Anal 11. No shields between the 

 dorsal fins or on the belly. Lateral shields 30, } depth of body, with serrated border 

 and moderately strong hooked spines. Caudal deeply bifurcate, with rounded lobes. 

 Pale olive above, white below ; fins white. 



Total length 90 millim. 



A single specimen. 



Closely allied to 0. hrevis Kner, which is distinguished by the longer dorsal spine, 

 the narrower humeral process, the longer adipose dorsal, and the number (13-14) of 

 anal rays. 



14. OXTDORAS ELONGATUS, sp. n. (Plate XL. fig. 4.) 



No teeth in the upper jaw. Depth of body 5 times in total length, length of head 

 3^ times. Snout obtusely pointed, covered with skin ; posterior nostril twice as distant 

 from the anterior as from the eye ; diameter of eye nearly twice in length of snout, 4^ 

 times in length of head. If in interorbital width ; cheeks and opercles covered with 

 skin ; cranial bones granulate ; fontanelle not produced as a groove posteriorly ; barbels 

 not branched, their bases united by the fold of the lower jaw ; maxillary barbels 

 extending to opercular cleft; mandibular barbels' short. Gill-cleft extending to below 

 posterior border of eye. Humeral process granulate and striated, twice as broad and 

 half as long as pectoral spine, tapering to a point posteriorly. Pectoral spine as long as 

 dorsal, nearly as long as head, extending to base of ventrals, strongly serrated on the 

 inner side, more feebly on the outer. Dorsal I 6 ; spine feebly serrated in front, more 

 strongly behind, equally distant from the end of the snout and the adipose fin. 

 Adipose fin not half as long as base of anal. Anal 12. No shields between the dorsal 

 fins or on the belly. Lateral shields 33, small, pluricuspid, with rather feeble hooked 

 spines. Caudal deeply bifurcate. Olive above, white below ; lateral shields and fins 

 orange. 



Total length 105 millim. 



A single specimen. 



Resembles most 0. humeralis Kner, which has minute teeth in the upper jaw, and 

 much larger lateral shields, their depth being about f that of the body and their 

 border bearing more numerous small spines. 



15. Callichthys armatus Gthr. 



16. Plecostomus emakginatus C. & V. 



