192 



THE PLAGIOSTOMIA. 



Acanthorhimis Blainv., 1816, Bull. Soc. philom., p. 121 (part). 



Spinax Cuv., 1817, Reg. anim., 2, p. 129 (part). 



Acanthias Risso, 1826, Hist, nat., 3, Poissons, p. 131 (part). 



Body elongate, subround, longer than the tail. Head flattened below. 

 Snout produced, tapering; nostrils transverse, remote from the mouth, inferior. 

 Orbit lateral, elongate. Spiracles behind the eye at a higher level. Mouth 

 wide, little arched, with a deep groove and with labial folds at each angle. Teeth 

 compressed, sectorial, alike in the two jaws, with oblique cusp and with cutting 

 edge nearly parallel to the edge of the jaw. Gill openings in front of the pectoral. 

 Each dorsal preceded by a spine which is not grooved on the sides, anterior near 

 the pectorals, posterior behind the ventrals. Tail with a pit at the root of the 

 caudal. Caudal with a produced subcaudal lobe, and without a notch below 

 the terminal portion. From Upper Cretaceous. 



Dorsal spine behind and remote from the inner angle of the pectoral 



acanthias (page 192) 

 Dorsal spine opposite or little behind the inner angle of the pectoral 



sucklii (page 194) 

 Dorsal spine near the axil of the pectorals, between the inner margins 



fernandinus (page 195) 



Squalus acanthias. 



Plate 14, fig. 1-4; Plate 43, fig. 9-10; Plate 59, fig. 1-2. 



'AKavBias yoKeos Aristotle, Hist, anim., book VI, c. 10, book IX, c. 37. 



Galeus acanthias Rondelet, 1554, Pise, p. 373; Gesner, 1558, Aquat., p. 716; Jonst., 1649, Pise, 



p. 27, pi. 8, f. 5; Klein, 1742, Hist, pise, miss., 3, p. 8, pi. 1, f. 5, 6; Duhamel, 1782, Traits, 4, 



sect. 9, p. 299, pi. 20. 

 Squalus sp. Artedi, 1738, Ichthyologia, Syn., p. 94, Gen., p. 66, no. 3, Descr. p. 102, no. 1; Gronow, 



1754, Mus., 1, p. 61, no. 134; 1763, Zoophy., 1, p. 34, no. 149. 

 Squalus acanthias Linne, 1754, Mus. Adol. Frid., p. 53; 1758, Syst., 1, p. 233; 1766, Syst., 1, p. 397; 



Block, 1784, Fische Deutschl., 3, p. 74, pi. 85; Bonnaterre, 1788, Ichth., p. 11, pi. 5, f. 12; 



SoiiN., 1801, Bloch Ichth., p. 135; Donovan, 1805, Br. fish., pi. 82; Turton, 1807, Fauna, p. 114; 



Risso, 1810, Ichth. Nice, p. 40; Faber, 1829, Fische Islands, p. 29; Jenyns, 1835, Man., p. 505; 



Fries & Ekstrom, 1836-57, Skand. fisk., p. 187, pi. 46; Gray, 1854, Gron. syst., p. 8; Jord. & Gilb., 



1882, Bull. 16, U. S. nat. mus., p. 16; Jord. & Everm., 1896, Bull. 47, U. S. nat. mus., p. 54; Jensen, 



1907, Dan. fiskc, p. 308, pi. 28, f. 3; Regan, 1908, Ann. mag. nat. hist., ser. 8, 2, p. 46. 

 The picked dog Brookes, 1763, Nat. hist., 3, p. 32; Pennant, 1769, Zool., 3, p. 77; Yarrell, 1836, 



Brit, fishes, 2, p. 400; Couch., 1867, Brit, fishes, 1, p. 49, pi. 11. 

 L'niquillat Broussonet, 1780, Mem. Acad, roy., p. 673; Lacepede, 1798, Poissons, 1, p. 270. 

 Spinax acanthias Cuv., 1817, Reg. anim., 2, p. 130; Richardson, 1836, Faun. Bor. Amer., 3, p. 291; 



Parnell, 1838, Mem. Wern. soc, 7, p. 420; Storer, 1839, Report fishes, p. 187; Bonap.\rte, 1841, 



Icon. Fauna Ital., Pesci; DeKay, 1842, N. Y. fish., p. 359, pi. 64, f . 210; Ayres, 1842, Bost. journ. 



nat. hist., 4, p. 288; Selys, 1842, Fauna Beige, p. 229. 

 Acanthias vulgaris Risso, 1826, Hist, nat., 3, Poissons, p. 131; Muller & Henle, 1841, Plagios., p. 83; 



Kroyer, 1853, Danm. fiske, 3, p. 868; Nilsson, 1855, Fisk. Skand., 4, p. 731; Kessler, 1859, Bull. 



Soc. nat. Mosc, 2, p. 473; Dum^ril, 1865, Elasm., p. 437; Bocage & Capello, 1866, Plagios., p. 21; 



