1913.] NATURAL SCIENCES OF PHILADELPHIA. 563 



way to caudal base. Adipose fin equals about f eye diameter, 

 inserted near last fourth in space between hind pupil edge and 

 caudal base. Anal inserted slightly before dorsal origin, first 

 branched ray longest, together with anterior rays, which elevated, 

 forms pointed lobe. Caudal a little longer than head, well forked, 

 and lobes pointed, upper slightly longer. Pectoral enlarged, about 

 equals length of head and an eye diameter, moderately low in its 

 insertion, upper rays longest. Ventral small, inserted about midway 

 between mandible tip and origin of adipose fin. ^>nt close before 

 anal. 



Color in alcohol pale brownish generally, paler on under surface. 

 Head brownish above, whitish below. Muzzle brownish, though 

 only including upper half of mandible. Suborbitals with rather 

 large, wide-set brownish dots. Iris slaty. Opercles and flanks 

 dusted with brownish, and behind dusky narrow lateral vertebral 

 blackish line to caudal base, which latter entirely blackish, though 

 area included less than eye. Median streak down back dusky, also 

 edges of scales on back sprinkled with minute dusky dots. Along 

 base of anal and close above on trunk, though nearly parallel, line of 

 dusky dots. Fins all pale, sprinkled with dusky dots on outer 

 portions. Adipose fin pale. 



Length 33 mm. 



Type, No. 39,309, A. N. S. P. Igarape de Candelaria, tributary of 

 the Madeira River, and approximately two miles distant, in Lat. S. 

 8° 45' W., Long. 63° 54', Brazil. September, 1912. Edgar A. Smith. 



No. 39,310, A. N. S. P., paratype Madeira River about 200 miles 

 east of W. Long. 62° 20', Brazil. September, 1912. Edgar A. Smith. 



No. 39,311, A. N. S. P., paratype. Tributary of the Madeira 

 River near Porto Velho, Brazil. January-February, 1913. Edgar A. 

 Smith. 



(Named for Dr. Franz Steindachner.) 



CHARACIN^. 

 TYTTOCHARAX gen. nov. 

 Type Tyltocharax madeirce sp. nov. 



Body oblong, well compressed. Head moderate. Snout short. 

 Eye large, without adipose eyelids. Mouth broad, short. Maxillary 

 free, oblique, with few simple conic teeth. Teeth in jaws conic, in 

 bands, and some externally similar ones on lips. Few symphyseal 

 teeth canine-like. Interorbital broad. Occipital process short and 

 triangular. Gill-membranes free from isthmus. Rakers minute. 



