1914.] 



NATURAL SCIENCES OF PHILADELPHIA. 



261 



illary 5; moutli witlth 3; interorbital 4; pungent dorsal spine 2; 

 first branched dorsal ray li; first branched anal ray 1|; least depth 

 of caudal peduncle behhid adipose fin 3; pectoral spine 1|; pectoral 

 fin 1|; ventral fin If. 



Body elongate, slender, compressed, deepest at dorsal origin and 

 tapers back gradually and slightly, edges all convex. Caudal 

 peduncle well compressed, least depth 1| its length, measured from 

 hind edge of adipose fin. 



Head small, depressed, profiles similarly and slightly convex, 

 swollen sides below broadly converge above, lower surface convex. 

 Snout broadly convex, length | basal width at front of eyes. Eye 

 ellipsoid, superior, centre slightly anterior in head length. Adipose- 

 eyelid not developed, ,and eyelids free. jNIouth moderately small. 



Fig. 12. — Rhamdella leptosotna Fowler. (Type.) 



with upper jaw slightly protruding, commissure very short. Lips 

 firm, fleshy. Maxillary extends about f in snout length. Teeth 

 in villiform bands in jaws, subequal in width, and each end of upper 

 band ends in posteriorly directed angle. Inner buccal folds narrow. 

 No other teeth in mouth. Tongue broad, fleshy, thick, depressed, 

 edges not free. Maxillary barbel very long, slender, reaches back 

 about half way in length of depressed last anal ray. Outer mental 

 barbel reaches to last^ or distal sixth of depressed pectoral spine. 

 Inner mental barbel reaches pectoral origin. Internasal spaces 

 subequal, anterior nostril near front snout edge in slight tube and 

 posterior nostril at last third in snout as simple pore. Interorbital 

 moderate, level. Bones on upper surface of head covered with 

 thiri skin, surfaces smooth. A narrow lengthwise median fontanel, 

 well defined most entire upper extent of cranium and ending pos- 



