PLEURONECTINvE 

 Genus 3. HIPPOGLOSSUS. 



Hippogtossus, Cuvier, 1817, R. Anim., ii, p. 221 [Pleuronectes hippoglossus 

 1835, Arch. Naturgesch., i (2), p. 164 ; Jordan and Evermann, rSgS, 

 xlvii(3), p. 261 1. 



Body rather elongate, compressed. Eyes on the right side, separated by a wide, 

 flat space, not broader than the orbit, the upper eye not placed on top of the head. 

 Olfactory laminas in moderate number, parallel, without central rachis. Mouth rather 

 large, oblique, the length of the maxillary more than J that of head ; jaws and dentition 

 about equally developed on both sides ; teeth strong, pointed, mostly curved, in two 

 or more series in the upper jaw and in one or more series in the lower ; vomer toothless. 

 Gill-rakers rather short, very stout, few in number ; lower pharyngeals narrow, 

 scarcely approximated anteriorly, each with two series of teeth, those of the inner 

 row very much larger than those of the outer. Dorsal fin with 93 to no rays, com- 

 mencing at a short distance behind nostrils of blind side and above eye ; rays simple 

 anteriorly, branched posteriorly, more or less scaled on both sides. Tip of first inter- 

 haemal spine projecting in front of anal fin, which has 71 to 85 rays. Pectoral fins 

 unequal, that of ocular side larger ; middle rays branched. Pelvic fins short-based, 

 subequal and subsymmetrical. Caudal fin lunate ; caudal peduncle slender. Scales 

 very small, adherent, cycloid, many of them with a small rough plate posteriorly ; 

 supplementary scales present. Lateral line with a distinct curve above the pectoral 

 fin. Vent median, between the pelvic fins. Vertebrae 50 to 51 (16 -f 34 — 35). 



Two species from Arctic and northern seas. 



Synopsis of the Species. 

 T Dorsal 98-106 (no), anal 73-80 (85) ; depth 2J to 2| in length ; supple- 

 mentary scales surrounding primary scales .... 1 . hippoglossus . 

 II. Dorsal 93-97 (100), anal 71-75 (78) ; depth nearly 3 in length ; supple- 

 mentary scales present, but not surrounding primary scales. 2. slenolepis. 



I. HIPPOGLOSSUS HIPPOGLOSSUS (Linnajus). 

 [Halibut.] 



Pleuronectes hippoglossus, Linnaeus, 1758, Syst. Nat., ed. 10, p. 269 ; 1766, ed. 12, p. 456 ; Bloch, 

 1783, Naturgesch. Fische Deutsch., ii, p. 47, pi. xivii ; Schneider, 1801, in Bioch, Syst. Ichth., 

 p. 147 : Lacepede, 1802, Hist. Nat. Poiss., iv, p. 601 ; Shaw, 1803, Gen. Zool. iv (2), p. 295 ; 

 Quensel, 1806, Vet. Akad. Handl., xxvii, p. 225 ; Nilsson, 1832, Prodr. Ichth. Scand., p. 57 ; 

 Valenciennes, 1851, in Trehouart, Voy. Isl. Groen., Zool., Poiss., p. 207, pi. xiv. 



Pleuronectes hippoglossus (part), Pallas, 1814, Zoographia, iii, p. 421. 



Hippoglossus vulgaris, Fleming, 1828, Brit. .\nim., p. r99 ; Yarrell, 1836, Brit. Fish., ed. i, ii, p. 

 230, fig. ; Storer, 1839, Rep. Ichth. Massach., p. 145 ; DeKay, 1842, N. H. New York (Fish.), 

 p. 294, pi. xlix, fig. 157 ; Varrell, 1859, Brit. Fish., ed. 3, i, p. 630, fig. ; Giinther, 1862, Cat. 

 Fish., iv, p. 403 : Malmgren, 1864, Arch. Naturgesch., xxx (l), p. 296 ; Storer, 1867, Hist. Fish. 

 Massach., p. 192, pi. xxx, fig. i ; Gilpin, 1869, Proc. Trans. N. Scotia Inst. N.S., ii (2), p. 30 ; 

 Collett, 1875, Vid.-Selsk. Forh., (1874), Till. p. 134-, CoUett, 1880, Vid.-Selsk. Forh., (1879), 

 p. 74; Day, 1880-4, Fish. Britain, ii, p. 5, pi. xciv ; Goode, 1881, Proc. U.S. Nat. Mus., iii, 

 (1880), p. 471 ; Moreau, 1881, Hist. Nat. Poiss. France, iii, p. 2S7 ; Collett, 1885, Nyt Mag. 

 Naturv. Christiania, xxix, p. 98 ; Lilljeborg, 1891, Sverig. Norg. Fiskar, ii, p. 282 ; Smitt, 

 1893, Scand. Fish., i, p. 409, pi. xvii, figs, i, 2 ; Goode and Bean, r895, Ocean. Ichth., p. 434, 

 pi. cv, fig. 363 ; Holt and Calderwood, 1895, Sci. Trans. R. Dublin Soc, (ii) v, p. 478 ; Jouan, 

 1897-1900, Mem. Soc. Cherbourg, xxxi, p. 223 ; Jespersen, 1917, Medd. Komm. Havundersog. 

 Kj0b., Ser. Fisk., v (5), p. 3 ; Huntsman, 1922, Contr. Canad. Biol., (1921), No. iii, p. 21 ; Schna- 

 kenbeck, 1925, Tier. Nord Ostsee, L. ii, xii (i), p. 3, fig. r ; Jensen, 1925, Medd. Havundersog. 

 Kj0b., Ser. Fisk., vii (7), p. 17; Jespersen, 1926, Rapp. proc. -verb, explor. mer., xxxix, p. 103; 

 Saemundsson, 1927, Rit. Visind. Isl., ii, p. 34 ; Schnakenbeck, 1930, in Joubin, Faun. Ichth. 

 Atlant. Nord, iii, fig. 



