DISCUSSION OF SPECIES AND THEIR DISTKIBUTIOK 381 



Ventrals composed of several rays, slightly io advance of the pectorals, which are narrow. 

 Bones flexible; mucous cavities of the head of moderate capacity. Pseudobranchiaj none. 



{Gihtthcr.) 



ONOS, Risso. 



Onos, Eisso, Hist. N.at. Eur. Mdrid., 1826, ill, 214 (type, G. )H«s(eH({ L.).— Gill, Proc. Acad. Nat. Sci. Pliila., 

 1S63, 240.— JoitDAN & CiLBERT, Bull., XVI, U. S. Nat. Mus., 796.— Collett, Vid. J5elsk. Forhaudl., 

 Cliristiania, 18U1, No. 11. 



Motclla, CuviER, Kigue Auimal, ed. 2, ii, 1829, 334. — Guntiier, Cat. FisL. Brit. Mus., iv, 364. 



Molvella and Motdla, Kali', Wiegui. Archiv., 1859, 90. 



Gadoids with body rather elongate, covered with minute scales; head not compressed; 

 upper jaw lunger; snout with 2 barbels and chin with 1; teeth on jaws and vomer in 

 bands; palatines toothless ; dorsal fins '2, the anterior composed of small fringe-like rays 

 concealed in a groove, preceded by a single hjng ray; second dorsal and anal long and 

 similar; caudal rounded or lanceolate; tail isocercal; ventral tins with liom 5 to 7 rays; 

 chin with a barbel. 



KEY TO THE SI'ECIES 01' ONOS. 

 [From Collett.) 



I. First ray <>f first dorsal short (erjual to or slightly longor thau snout). 



A. Pectoral rays about 14 [O. pacificcs] 



1. Pectoral rays about 17. 



a. Lougitiidiual diameter of eyes equal to or less thnn width of iuterorlntal space. 



* Height of body 7 J iu total length, v. 6 O. meditekranevs 



••Height of body 6 J in total leugth, v. 7 O. guttatus 



h. Lougitudiual diameter of eyes greater thau width of interorbital space. 



* Head large, its length about 4A iu total [O. m.\cropthalmu.s] 



**HeaiV small, its leugth about 5.i in total O. lilSUAYEXSIS 



2. Pectoral rays 22 or more. 



a. Lougitudiual diameter of eye eijual to or less tliau iuterorl)ital space. 



First ray of first (bursal eciual to diameter of eye O. vulgahis 



First ray of first dorsal greater than diameter of eye O. keinhakdtii 



h. Longitudinal diameter of eye great, larger thau interorbital .space O. carpenterii 



II. First ray of first dorsal loug (equal to head), color uniform salmou or brick red O. ENSls. 



ONOS ENSIS, (Reixiiardt), Gill. (Figure 327.) 



Motellaensis, Reixhardt, Kon. Ved. Selsk. Math. Natura, Copenhagen, vi, 1837; ex. vii, 1838; 116, 128. — Col- 

 lett, Forh. Vid. Selsk. Christiania, 1878, No. 17; Norske Nordhavs Exp., 1890, Fish, 134. — LCtken, Vid. 

 Medd. Naturh. Foren. Copenhagen, 1881, 236. 



Onoa eiisis, Gill, Proc. Acad. Nat. Sci., Phila. 1863, 241. — Jordan and Giliiert, Ikill. xvi, U. S. Nat. Mus- 

 797. — GiJXTnER, Challenger Report, xxii, 98. — Collett, Forh. Vid. Selsk, 1891, No. 11. 



Onos rufiis, Gill, Pr,oc. U. S. Nat. Mus., vi, 1883, 259.— Jordan, Cat. Fish. N. A., 128. 



Head small, its length 5i^6 in total. Eye small, its diameter one-half the length of 

 the snout. Vent nearly median. First dorsal rays prolonged, as long as head. Teeth in 

 villiforni bands, small and uniform. 



Eadial formula: D. 59; A. 44-40; P. 22-27; V. 8. 



This form is known from (xreciiland, whence the museum at Copenhagen obtained 2 

 specimens, taken in lS3(i from the stomach of a seal (('i/stophoni) at Oinenak (lat. 70^ N). 

 Another was found iu 1882 by the U. S. Fish Commission steamer Fish Hawk in lat. 40°, off 

 the coast of New Jer.scy, in 1,10G fathoms. 



The body is unusually high, the greatest height at anus contained 4i times in length ex- 

 clusive of caudal. The head enters 5.J times iu the length to end of caudal peduncle and 

 C times iu total length; its width at cheeks equals two-thirds of the head's leugth. 



The eyes are rather large, nearly as long as snout and the interorbital area, and are 

 entirely in tlie anterior half of head, the ]»osterior margin of the orbit nearly ecpiidistant 

 between the tip of the snout and the posterior margin of the operculum. The moutli is 



