PROCEEDINGS OF UNITED STATES NATIONAL MUSEUM. 279 



Lateral line very prominent, as in H. exilis, the tubes coarse, their 

 number (88 to 92) less than that of the transverse series of scales. 



Scales : 41 to 50 ; 110 to 120 ; 35 to 44. 



Lateral line slightly rising anteriorly, but without arch. No acces- 

 sory lateral line. Eays of all the fins on the eyed side (except the 

 posterior part of dorsal and anal) and of the caudal on the left side 

 covered high up with series of narrow- ctenoid scales. 



Fins well developed, of firm texture, the tips of the rays protruding. 



Dorsal fin beginning immediately in front of the pupil, its anterior 

 rays low, the others regularly increasing backwards to a point much 

 behind the middle of the fin, then becoming rapidly shorter, the highest 

 rays nearly half the length of the head and more than the length of the 

 caudal peduncle. 



Anal fin preceded by a spine, its highest rays opposite to or in front 

 of those of the dorsal and equal to them, the others rapidly shortened. 

 Caudal long, double -truncate or convex, the middle rays considerably 

 l)roduced, as in H. exilis, more than in H. jordani. 



Pectoral fin half the length of the head, that on blind side shorter. 

 Yentrals moderate, reaching past front of anal, their inner rays short- 

 ened. 



Dorsal rays, 77 to 84; anal rays, 59 to G3; ventrals, G. 



Color light olivaceous brown, nearly uniform on the body. Fins 

 grayish, obscurely and irregularly blotched with dusky. Blind side 

 plain. 



This species differs from Hippoglossoides jordani and H. exilis, the two 

 species thus far known fiora the Pacific coast of the United States, in 

 the presence of but a single row of teeth in the upper jaw. From 11. jor- 

 dani it further differs in the much smaller teeth, fewer fin rays, and 

 more convex caudal. From H. exilis the small scales and firmer texture 

 at once distinguish it. Its nearest relative is probably the Atlantic 

 species, Hippoglossoides platessoides, which has a larger number of rays 

 in the vertical fins. 



Hippoglossoides elassodon is known to us by about 20 examples of 

 different sizes, all obtained with hook and line from the wharves at 

 Seattle and Tacoma, in Washington Territory. 



