46 



TRICHIURID^. 



TRICHIURUS LEPTURUS, Linn. [No. 17545]. ^ « 



Trichiurus lepturus, Linn., Syst. Nat., i, 17GG, 429.— Bl. Schn., Syst. Ichth., 1801, 517.— 

 Cuv. & Val., Hist. Nat. des Poiss., viii, 1831, 237.— Yarrell, British Fishes, 

 i, 1841, 204. — Stoker, Boston Jour. Nat. Hist, iv, 1844, 181.— Casteln. 

 Anim. nouv. ou rares Amer. Slid, 1855, 24. — Dekay, Zool. New York, Fishes, 

 1842, 109, pi. 12, f. 35.— GuiCHEN, Poiss. in Romon de la Sagra, Hist. Cuba, 

 1845, 105.— Gunther, Cat. Fishes, ii, 1860, 34G. 



Trichiurus argenteus, Shaw, Zool., iv, 1803, 90, pi. 12. — Mitch., Trans. Lit. and Phil., 

 Soc, New York, i, 1815, 364. 



Lepturus argenteus, Gill, Proc. Acad. Nat. Sci., Phila., 1863, 226. 



The height of the body, at the situation of the pectoral fin, is con- 

 tained 17^ in the total length, and the length of the head is 7 times 

 in the same. The eye occupies half of the depth of the head ; its di- 

 ameter is slightly more than the interorbital space, and it is contained 

 6 times in the length of the head and 1^ times in the length of the 

 snout. The latter is 3J times in the head-length. Height of pectoral 

 fin is § of the height of the body, and is contained 26| times in total 

 length ; tail, from the extremity of the dorsal fin, 5| in the same, and 

 from the last spine on the lower surface of the body, 10^ times. Anus 

 placed at the junction of the anterior and middle thirds of the length; 

 behind anus are 98 small spines. Dorsal rays, 122 ; pectoral, 11. Lat- 

 eral line below the middle of the body. Silvery, with a dark metallic 

 luster along the back. Length, 10.50. 



Locality: Mouth of the Colorado River, Gulf of California. 



We do not hesitate to refer this species to the Trichiurus lepturus as 

 it is illustrated by specimens comiug from the Gulf of Mexico, which are 

 found to have a relatively longer tail. Giinther's statement that the 

 diameter of the eye is contained three times in the length of the snout 

 is an error, if applied to the Western Atlantic species. We have meas- 

 ured nine specimens, obtained from seven different localities on the 

 Atlantic and Gulf coasts, and find it to vary from If to 2f. In four 

 specimens the snout was twice the diameter of the eye, in three it was 

 more than twice, and in two it was less than that number. We have 

 not been able to find any good specific characters for the different species 

 of Trichiurus. The species are founded principally upon locality and 

 the relative proportions of the different parts of the body ; yet if all 



