Jordan and Ever maun. Fishes of North America. 1929 



anal ray equals least height of tail and is slightly more than that of fifth 

 to eighth, which are longest, the last ray .1 as long as orbit; vent nearly 

 midway between origin of veutrals and that of anal; caudal distinctly 

 emarginate when fully expanded, the length of middle rays 9 times, and 

 that of the external rays TV,, times in length of body. The structure of 

 the pectoral is similar to that in Trif/Jops pinf/di, but the longest of the 

 exserted lower rays extends considerably farther back than the upper por- 

 tion of the fin. The origin of the pectoral is directly under that of the 

 spinous dorsal. The length of the longest exserted ray (eleventh) is con- 

 tained 44 times in the standard body length. Five of the lower pectoral 

 rays are modi lied. The tenth pectoral ray, which is the longest of thenon- 

 exserted portion, is only about % as long as the eleventh and extends to near 

 jhe end of the spinous dorsal. The ventral is situated farther in advance 

 than in Triglops pimjdi, and does not quite reach to the vent when extended. 

 Its length is contained nearly 12 times in the unit of length. Colors: 

 There are traces of the same % bars which ornament the back and sides of 

 Triglopv pinyi'li, but the dorsal portion of the markings is very faint and 

 the. lower limits of the dark areas are the most intense and form a succes- 

 sion of elongate blotches along the median line of the body, partly below 

 and partly on the lateral line; dorsal tins with 3 series of dark spots on 

 the rays and spines, but not on the connecting membrane; these spots 

 forming broken bands which are oblique on the first dorsal and nearly 

 horizontal on the soft dorsal when the tins are raised; a crescent-shaped 

 broken band crosses the top of the body at the ninth dorsal spine: a 

 short, dark blotch near the root of the pectoral on the tenth, eleventh, 

 and twelfth rays; another dusky blotch in the upper axil of the pectoral; 

 4 dusky bars on the pectoral, the iirst of which is very short, involving 

 only about 5 of the rays, the second and third extending to the first 

 exserted ray, and the fourth, which is near the tip of the fin, extending on 

 the 7 upper rays only; caudal dusky at the base and with 4 bars, the 

 first of which is faint in the middle and the last interrupted by the emar- 

 gination of the tin; lips and upper portion of the maxilla dusky; a dark 

 blotch on the iuteropercuiuni ; membrane lining the inner surface of the 

 operculum dusky ; ventrals and anal whitish. Length 172 mm. (Bean.) 



Concerning this species Dr. Gilbert observes : 



"The elongation of the lower exserted pectoral rays, and the ' serrations 7 

 (i. e., minute spinous scales) on the fin rays, are characters which Prionis- 

 tius shares with related species of Triylops. The slenderness of the body, 

 the emarginatiou of the caudal tin, and the elongate dorsal and anal fins 

 are present and the two former carried to an extreme in Elanura forficata. 

 In addition to these characters, Prionistins has the breast naked and the 

 dorsal region without the usual series of enlarged plates." 



Three specimens, 77 to 87 mm. long, were secured at stations south of 

 Sannak and north of Unimak Islands, Alaska, at 38 and 56 fathoms. The 

 ventral fins seem to be not more advanced in position than in the other 

 species. In other respects these specimens agree well with Bean's admira- 

 bly full description. Aleutian Islands, south to British Columbia; not 

 rare, (niacellntt, diminutive of mace/ 1 , slender or thin.) 

 3030 44 



