412 CONTRIBUTIONS TO NORTH AMERICAN ICHTHYOLOGY IV. 



651. S. piCMda Blocli »& Schneider. — Piciida ; Barracuda. 



Origin of first dorsal opposite ventrals, far in advance of the middle 

 of the bod}', at the tip of the pectorals. Interspace between dorsals one- 

 fifth of total length. Pectoral fins one-eleventh of total length. Scales 

 large. Head Sj in total length; depth 7|. D. V-I, 9; A. I, 9; scales 

 9-83-15. Vertebrae 12 + 12. L. 3^ feet. {Gilnther.) West Indies, 

 north to Florida. 



(Bloch & Scbneider, 1801, 110: Sphi/raina barracuda Cnv. & Val. iii, 343; Giintlier, 

 ii, 33G; Goode & Bean, Proc. U. S. Nat. Mus. 1879, 14G.) 



Family LXVIII.— POLYNEMIDJE. 



[The Thread-fins.) 



Body oblong, compressed, covered with rather large scales, which are 

 feebly ciliated or smooth; lateral line continuous, extending on the cau- 

 dal fin. Head entirely scaly ; snout conic, projecting over the horizontal 

 mouth, which is rather large, the maxillary extending to beyond the eye. 

 Eye lateral, anterior, large, with a largo adipose eyelid. Villiform teeth 

 on jaws and palatines and usually on vomer also. Pseudobranchise con- 

 cealed. Branchiostegals 7. Gill-membranes sei^arate, free from isth- 

 mus. Gills 4, a slit behind fourth. Dorsal fins 2, well separated, as 

 in the Percesoces, the first of about 7 feeble but rather high si)ines, the 

 second rather larger, of soft rays. Anal fin similar to the soft dorsal, 

 sometimes larger; caudal fin widely forked; second dorsal, anal, and 

 caudal fins usually covered with small scales ; ventrals I, 5, thoracic, 

 but placed well behind the pectorals; pectoral fins moderate, placed 

 low, divided into two parts, the lower and anterior portion composed 

 of several filiform articulated apjiendages, free from each other, organs 

 of touch. Bones of skull with a well-developed muciferous system, as 

 in Sciccnidw. Basis cranii double, with tube ; post-temporal bifurcate ; 

 scapula with median foramen; superior j)haryngeal bones 4, third 

 largest, narrow, directed forward. Basal j)ectoral bones divided ; two 

 normal, supporting the fin, one longitudinal without rays, and one a 

 plate on the coracoid, supporting elongate rays. Stomach coecal, with 

 a few pyloric appendages. Air-bladder various, sometimes wanting. 

 Vertebra? 24. Genera 3 ; species 25. Troj)ical seas. A singular grouj), 

 in some respects intermediate between Sciwnidce and Mugilidcc, but not 

 closely related to any other of our fishes. Most of them are valued as 

 food fishes. 



{Pohjnemidcc Giinther, ii, 319-333.) 

 a. Vomer witli teotli ; preopercle serrate ; anal fin not much larger tlian second dor- 

 sal POLYXEMUS, '203, 



