57. SCOMBERESOCID^E - IIALOCYPSELUS. 377 



fins not scaly. Caudal moderately forked, the middle rays being twice 

 the length of the eye. Pectorals shorter than postorbital part of 

 head. Ventrals a little shorter. Back broad. Head (with lower 

 jaw) 2. D. 14; A. 14; Lat. 1. 03. Southern California, not very 

 common. 



(Jordan & Gilbert, Proc. U. S. Nat. Mus. 1880, 335.) 



aa. Pectoral 1ms very long; ventrals very short ; body very slender. (Euleptorham- 

 J;//M* Gill.) 



6O5. II, loaogirosiris Cuvier. 



Olivaceous, sides silvery. Body extremely slender and elongated, 

 much compressed, almost band-like. Back thin, subcariuate. Lower 

 jaw very slender and long, much longer than the rest of the head. 

 Teeth very feeble. Eye large, about equal to snout. Pectoral fins 

 long and slender, half as long as mandible, more than one-fourth the 

 length of the rest of the body. Upper rays of pectorals broad and 

 compressed. Ventrals not longer than eye, inserted far back. Caudal 

 fin unequally forked, the lower lobe the longer. Head 6rf; depth 10. 

 Mandible about 3. D. 22; A. 19; V. G. L. 18 inches. Cape Cod to 

 Indian Ocean, in the open sea; rare on our Atlantic coast. 



(Cuvier, Eegne Anim. ; Giiuther, vi, 276: Hemirhamphus macrorhynchv& Giintlier, vi, 

 27G: Euleplorhamphus longirostris Putnam, Proc. Bost. Soc. Nat. Hist. 1870, 238.) 



184. HALOCTPSELUS Weinland. 



(Weinlaud, Proc. Bost. Soc. Nat. Hist. 1839, vi, 385: "type Exoccetus mesoyasicr Mitch.") 

 This genus differs from Exocostus mainly in the anterior position and 

 small size of the ventral fins, which terminate in advance of the anal 

 fin, and are not used as organs of flight. Species not very numerous. 

 sea; xu<^Ao?, a swallow.) 



6OG. II. evoJacas (L.) Weinl. 



Olivaceous above, with dark specks; silvery below, with a bright blue 

 lustre. Pectoral fins black above and behind, the lower border whitish. 

 Snout obtuse and short, f the diameter of the eye. Eye not large, 4 

 in head, less than the width of the broad, rather con\ ex, iuterorbital 

 space. Distance from snout to first ray of ventral about equal to dis- 

 tance between root of ventrals and last ray of dorsal. Pectoral fins 

 long, the length of the body, reaching the root of the caudal ; second 



*Gill, Proc. Acad. Nat. Sci. Phila. 185 ( J, 131: type Eulcptorhamphus brevoorti Gill = 

 Hcmirhamphus longirostris Cuvier. (zvXeitroS, very slender; pajntpo?, beak.) 



