430 PROCEEDINGS OF THE ACADEMY OF [Oct. , 



profile. Tail very long, compressed at first or with its width a trifle 

 less than its depth, then soon becoming quadrangular, and tapering 

 rather suddenly into a strong point. 



Head small, deep and compressed. Snout short, robust, its least 

 depth about midway in its length, and its greatest width about 1^ in 

 greatest distal depth of muzzle. Eye small, a trifle longer than deep, 

 and its center falling a trifle before middle in length of head. Mouth 

 moderately small, terminal, superior, and with rather thin jaws 

 slightly protruding above and below. Nostrils small, together, close 

 to middle of front rim of eye. Interorbital space narrow, concave, 

 forming an isosceles triangle, with angle about -| an eye-diameter 

 anterior to eye. 



Gill-opening about f of eye, vertical, and laterally superior on nape 

 near nuchal keel. 



Coronet moderately elevated, forming a trenchant Iceel, which is very 

 slightly convex in profile and with a slight level space posteriorly at 

 summit. Ridge of coronet on each side anteriorly with a slight tu- 

 bercle and posterior edge with a slight tubercle also at each side. Below 

 former, on each side of head, a large elevated tubercle. A trenchant 

 and slightly elevated keel at front of interorbital angle, and each side 

 of triangle separated from this though gradually springing up into a 

 high broad bony process above posterior margin of eye. A very 

 obsolete postorbital tubercle near eye. Shoulder-girdle with 3 large 

 rounded tubercles. Opercle with many fine radiating striae. Head 

 without any filaments. Body-rings mostly with concave surface.s, 

 without spines, though ridges slightly asperous and forming slight 

 tubercles on those on trunk more or less, though none distinctly 

 enlarged at intervals. On tail ridges become more or less obsolete , 

 especially towards tip, though those forming longitudinal edges distinct. 



Fins rather small, with simple rays. Dorsal with long base, begin- 

 ning on middle of tenth ring, though appearing in profile close to its 

 anterior edge, and then extending on to fourth caudal ring, towards its 

 posterior margin. Anal small, short, just before ridge of ihird ring on 

 tail. Pectoral with a broad base and rays all rather short. Vent a 

 little before anal. 



Color in alcohol faded dull brownish, head and ridges of rings all 

 pale. liOwer side of head with some few brownish spots, all a little 

 smaller than pupil. Fifth, sixth and seventh, tenth, eleventh and 

 twelfth of body-rings, and third and fourth, ninth and tenth, thir- 

 teenth and fourteenth, seventeenth and eighteenth, twentieth, twenty- 

 first and twenty-second, and most likely beyond on tail, all deeper 



