1908.] NATURAL SCIENCES OF PHILADELPHIA. 319 



DESCRIPTION OF TRACHYPTERUS SELENIRIS, A NEW SPECIES OF RIBBON- 

 FISH FROM MONTEREY BAY, CALIFORNIA. 



BY .JOHN OTTERBEIN SNYDER. 



Early in June of last year a large Ribbon-fish was found almost 

 stranded on the beach at Monterey, California. It was secured by Mr. 

 Frederick A. Wood worth, of Pacific Grove, and through his kindly 

 interest sent to Stanford University for identification. Its close 

 resemblance to Trachyptcrus ishikawce^ of Japan was at once apparent, 

 but a detailed examination was impossible at that time on account of 

 the decayed condition of the specimen, the delicate silvery skin leaving 

 the body at a touch of the finger, and the muscles almost parting from 

 the bones. After a long immersion in a mixture of strong alcohol and 

 formalin, it may now be handled without further injury. 



When the IVIonterey specimen is compared with the type of Trachyp- 

 terus ishikaivce, certain differences appear which indicate that we have 

 to deal with two distinct species, one of which, being unknown, is here 

 described as Trachypterus seleniris. The latter differe from T. ishika- 

 wce, the most nearly allied form, in having a more slender body, a 

 smaller head, a smaller eye, and a weaker armature of the body. The 

 chief differences may be tabulated thus : 



T. seleniris. T. ishikawce. 



Length in millimeters 1520 1650 



Head in length 9^ times. 8| times. 



Depth near middle of body 11 " 7| " 



Depth at beginning of posterior third ISi " 14 " 



Diameter of eve 32 " 25 " 



Length of maxillary 25 " 22 " 



Trachypterus seleniris n. sp. 



Head, 9^ in the lengtJi; depth, 9|; eye, 3| in head; dorsal rays, 168; 

 pectoral, 9. 



Length of head greater than its depth, about equal to depth of body 

 in region of pectoral ; snout 3 in head ; width of interorbital space 2 in 

 diameter of eye ; lower jaw projecting slightly beyond the upper ; 



^ Trachypterus ishikaivce Jordan and Snyder, Journal of the College of Science, 

 Imperial University, Tokyo, Vol. XV, Pt. 2, p. .310, PI. XVII, fig. 10; Smithsonian 

 Miscellaneous Collections, 45, p. 240, PI. LXIII. 



