430 CONTRIBUTIONS TO NORTH AMERICAN ICnTITYOLOGY - IV. 



the genus .U/;.s." Species of smaller si/.e than the Tunnies, mostly 

 pelagic. (Bainl.) (zu, true; Ou^<>;, tunny.) 



OTN. E. allitcrutllS (Raf.) J. & G. Little Tunny; Albicorc. 



IHiiisli above with wavy, blackish, longitudinal streaks; silvery 

 below. Inferior margin of preoperculum half longer than posterior. 

 Dorsal spines moderate; pectorals reaching the vertical from the ninth 

 dorsal spine. Head 3 in length ; depth 4!. D. XV-I, 12-VIII ; A. I, 

 12-VII. Atlantic Ocean ; occasional on our coast. 



5 uniln-i- iiHUi-rutH* Raf. Carat trri <li Alcuni Xuovi Geueri, 1810, 4!i : Thy nuns afliiii*, 

 tliiiiniiiHi, ami breriroxtris Giiutlirr. ii. ,'ii :'-'. !t>5.) 



G75). E. pclliJIiys (L.) Liitkon. Oct-anic Bonito. 



Back bluish ; on each side of the belly 4 brownish longitudinal bauds. 

 Length of posterior margin of the preoperculum 1 in that of the in- 

 ferior. Pectoral reaching the vertical from the tenth dorsal spine; dor- 

 sal spines rather feeble. Ilead 3i; depth 4 (to fork of caudal). D. 

 XV-I, 12 + VIII; A. II, 12 + VII. (Giinther.) Tropical seas; occa- 

 sional on our Atlantic coast. 



L. Syst. Nat.: Thi/nnus pdamijs Giinther, ii, 305: Thynnua pdamijs 

 Cuv. ! V:il. viii, IK?.) 



FAMILY LXXV. CxVRANGIDJE. 



The Pilot -fiKhet. 



Scombroid fishes, with the body more or less compressed and often ele- 

 vated, sometimes naked, or more usually covered with small, thin, cycloid 



lies. Head compressed, the occipital keel prominent, usually trench- 

 ant. Month of varying size, the dentition various, the teeth generally 

 small : prcmaxillaries usually ]rotractile ; maxillary with or without a 

 supplemental bone; preoperele usually entire in the adult, in the very 

 NIIMIIL; armed with three or more spines.* Lateral line complete, anteri- 

 orly arched, the posterior part straight, sometimes armed with bony 

 plates. Dorsal fins more or less separated, the spinous part rather weak, 

 the spines usually depressible in a groove; anal tin long, similar to the 

 soft dorsal, always preceded by t wo st ill' spines, usually separate, but in 

 the young often more or less connected wifli the tin or with each other; 

 these sometimes disappear with old a-c, and s ..... etimes the spinous dor- 

 sal also vanishes; often a procumbent spine before the dorsal tin; ven- 

 tral tins thoracic, well developed, I , ." : caudal peduncle very slender, the 

 I'm \\idelyforked; pectoral tins narrow, dill openings very wide, the 

 membranes usually not united, free from the isthmus, dills 1, a slit 



uf tli' transformations of enrioas members of this family, see LUt- 

 Atlantica, 



