1906.] NATURAL SCIENCES OF PHILADELPHIA. 465 



ing, flattened towards tip, pyramidal, and mandible rather broader with 

 convex surface or of swollen appearance. Profile of snout a little 

 convex at first, then merging into nearly straight upper profile of 

 head. Profile of mandible at first a little concave, then a little convex. 

 Eye a little posterior in head, high, and a trifle longer than deep. 

 Mouth forming a slight arch. Lips not evident except as a narrow 

 cutaneous fold along margin of mandible. Maxillary narrowly exposed 

 obhque, and extending distal extremity posteriorly till about opposite 

 posterior margin of pupil. Edge of maxillary with fine teeth. Tip of 

 upper jaw a hard or tough point. Teeth in jaws uniserial, rather 

 small, of more or less equal size, compressed or cultrate, crowded one 

 after the other and all directed backwards. Wlien jaws close upper 

 teeth slip over sides of mandibular. In front of upper jaw a A- 

 shaped patch of conic teeth progressing in size to outermost, which is 



:r 



Fig. 51. — Belonocharax beani Fowler. 



thus canine-like. There are also several other smaller conic teeth 

 still exterior to latter. No teeth at symphysis of mandible. On roof 

 of mouth near front of upper jaw on each side, a short series of several 

 rather irregular small denticles. Buccal membranes broad, reaching 

 first f in length of jaws. Tongue flattened, free, rounded as viewed 

 from above, and its tip falling about last f in length of snout. Bones 

 of head all more or less finely rugose-striate. Opercular flap rather 

 broad. 



Gill-opening extending forward about opposite anterior margin of 

 pupil. Gill-rakers about 8 + 11 short denticles, longest barely more 

 than half of pupil. Filaments about f of orbit. Isthmus narrow, 

 slender, edge rounded. Bones of shoulder-girdle, where exposed, with 

 slight striae. 



Scales large, of more or less uniform size, each one striate and 

 ctenoid. Scales on breast and bases of caudal and anal smaller than 



