240 SMITHSONIAN MISCELLANEOUS COLLECTIONS [vOL. 45 



Family TRACHYPTERIDyE 

 TRACHYPTERUS ISHIKAW^ Jordan and Snyder 



(Trachyptcnis iijiincc Jordan and Snyder; young) 

 (Plate LXIII) 



Two specimens about 172 centimeters long were " taken at the 

 surface in a dying state off Mera on the west coast of Bashu, near 

 the mouth of Tokyo bay." 



Trachypterus iijiincc is probably an example of the young of this 

 species, the type specimen of which had about 198 dorsal rays. 



Head 8 in length, depth 7^4, dorsal 168, pectoral 9. Length of 

 head somewhat greater than its depth, the latter equal to distance 

 between tip of snout and posterior border of eye ; snout 2^/3 in 

 head; eye 33^, 37/3 in depth of body; width of interorbital space 

 i^ in diameter of eye; lower jaw projecting slightly beyond the 

 upper ; process of premaxillary extending to a vertical through 

 posterior border of eye ; maxillary with a leaf-shaped flap a little 

 longer than diameter of eye, with branched striations extending 

 outward from its point of attachment ; opercular bones with con- 

 spicuous striations. Teeth very weak ; 2 or 3 small, loosely im- 

 bedded ones on vomer, a row of 4 on the premaxillary, 3 or 4 on 

 each side of symphysis of lower jaw. Gill-rakers on first arch 

 5-|-iij provided with tooth-like sets on the inside; filaments of 

 pseudobranchise equal in length to those of the gills. 



Origin of dorsal above upper edge of gill opening, the rays highest 

 near beginning of posterior third of body, where they are about i^ 

 times the diameter of orbit. Length of pectoral equal to diameter 

 of orbit. Ventral fins absent or represented by a mere filament, 

 the place of insertion indicated by a narrow groove below posterior 

 edge of base of pectoral. Caudal projecting upward; filaments 

 absent, possibly broken. Several small spines projecting down- 

 ward and backward from end of caudal peduncle. 



Head naked ; body closely covered with minute pads or plates 

 containing a varying amount of bony matter ; those on median part 

 of the ventral surface pointed, hard and white like enamel ; along 

 dorsal part of body enlarged plates are arranged in vertical rows 

 parallel with the mterneurals. Lateral line with large, quill-like 

 tubes, beginning at upper edge of gill opening, gently bending down- 

 ward and extending along body somewhat below the median line ; 

 armed near caudal fin with a few weak spines. 



Color dusky, ventral surface and a narrow area along base of 

 dorsal darker. 



