Fishes of the Western North Atlantic 487 



30, 1916: 36 (in list); Saemundsson, Vidensk. Medd. naturh. Foren. Kbh., 7^, 1922: 167 (depth, 

 occur. Iceland) ; Bigelow and Welsh, Bull. U.S. Bur. Fish., 40 (i), 1925: 52, 551 (diagn., ill., general, 

 in W. Atlant.) ; Jensen, Rapp. Cons, explor. Mer., 59, 1926: 98, loi (south side of Davis Strait ridge); 

 Breder, Field Bk. Mar. Fish. Atlant. Coast, 1929: 25 (general); Jordan, Evermann and Clark, Rep. 

 U.S. Comm. Fish. (1928), 2, 1930: 21 (listed, Greenland seas, Gloucester, Nova Scotia Banks) ; MacCoy, 

 Bull. Boston Soc. nat. Hist., 69, 1933: 8 (240 miles ESE. from Boston Lightship) ; Bigelow and Schroe- 

 der, Canad. Atlant. Fauna, biol. Bd. Canad., 12^, 1934: 18 (general); Vladykov and McKenzie, Proc. 

 N. S. Inst. Sci., rp, 193;: 49 (off Nova Scotia) ; Fowler, Bull. Amer. Mus. nat. Hist., yo (i), 1936: 83 

 (descr., ill. of Georges Bank spec, discuss, of ident. of Morocco spec. rep. by Vaillant, 1888) ; Lubbert 

 and Ehrenbaum, Handb. Seefisch. Nordeurop., 2, 1936: 287 (Iceland). 

 Not Centroscyllium fahricii Lahille, Enum. Feces Cartilag. Argent., 1 921: 16 (Falkland Is.); Pozzi and 

 Bordale, An. Soc. cient. argent., 120, 1935: 10 (Argentina, Lat. 52° S.) ; these doubtless refer to the 

 type specimen of C. granulosum Giinther, 1 880. 



Genus £/wo^;(?rMj Rafinesque, 18 10 



Etmopterus Rafinesque, Carratt. Gen. Nuov. Sicil., 1810: 14; type species, E. aculeatus Rafinesque, 1810, 

 equals Squalus sfinax Linnaeus, 1758. 



Generic Synonyms: 



Ac<mthorhinus (in part) Blainville, Bull. Soc. philom. Paris, 1 8 16: 121. 



Sfinax Cuvier, Regne Anim., 2, 1817: 129; type species, Squalus sfintue Linnaeus, 1758. 



Acanthias (in part) Risso, Hist. nat. Europ. Merid., j, 1826: 132. 



Centring (in part) Lowe, Proc. zool. Soc. Lond., 1833: 144; type species, C. nigra Lowe, equals Squalus sfinax 



Linnaeus, 1758; not Centrina C\x\\tT, 1817. 

 Acanthiiium Lowe, Proc. zool. Soc. Lond., 1839: 91 ; type species, A. ptsillum Lowe, 1839, designated by 



Goode and Bean (Smithson. Contr. Knowl., 30, 1895: lO; Mem. Harv. Mus. comp. Zool., 22, 1896: 



10^). 

 Acanthidim Sollas, Zool. Rec, 43, 1906: 58 (obvious misprint for Acanthiiium') . 



Generic Characters. Squalidae with dorsal spines largely exposed, arising at origins 

 of fins and lying along anterior margins of latter; trunk slender, subcylindrical, the pe- 

 duncle without lateral ridges or precaudal pits; snout in front of mouth is somewhat 

 shorter than from front of mouth to origin of pectorals; upper and lower teeth unlike, the 

 former with several cusps, the latter with only i cusp, deeply notched outwardly and so 

 oblique as to form a continuous cutting edge; dermal denticles ranging from bristle-like 

 to scale-like; eyes and spiracles large; anterior margin of nostrils with a long, narrow- 

 triangular lobe; a voluminous triangular pit at corner of mouth and a labial furrow on each 

 jaw; dorsals triangular, their free rear corners elongate but not very slender; origin of ist 

 dorsal posterior to tips of pectorals; 2nd dorsal larger than ist, its origin over or posterior 

 to base of pelvics; caudal truncate, with well marked subterminal notch, but without defi- 

 nite lower anterior lobe, its axis only very slightly raised; pectorals brush-shaped, their 

 inner corners rounded and not at all produced; inner edge of anterior part of upper eyelid 

 deeply pigmented; some of the species, perhaps aU of them, with luminous organs.^ 



1. We agree with Fowler (Bull. U.S. nat. Mus., 100 [r^], 1941: 246) that Acanthiiium Lowe is a synonym of 

 Etmofterus Rafinesque, and that the species grouped under A canthidium by Garman (Mem. Harv. Mus. comp. 

 Zool., 36, 1913: 215) fall properly in Deania Jordan and Snyder, 1902. See also footnote 4, p. 451. 



2. For a general account of these organs, see Daniel (Elasmobranch Fishes, Univ. Calif. Press, 1934: 29). 



