Fishes of the Western North Atlantic 455 



ters they are separated, must await comparison of specimens from the three geographic 

 regions. 



Because of these uncertainties the following Key is limited to the western Atlantic 

 representatives of the genus, with the Mediterranean and eastern Atlantic blainville in- 

 cluded to facilitate comparison. 



Key to Western Atlantic Species 



I a. First dorsal spine over or posterior to inner corner of pectoral; midpoint of bases of 

 pelvics much nearer to origin of 2nd dorsal than to rear end of base of ist dorsal; 

 anterior margin of nostril expanded as a simple lobe. 



acanthias Linnaeus, 1758, p. 455. 

 lb. First dorsal spine about over midpoint of inner margin of pectoral; midpoint of 

 bases of pelvics about midway between rear end of base of ist dorsal and origin of 

 2nd dorsal; anterior margin of nostril usually with a small secondary lobe. Fig. 87 F, 

 89 B. 

 2a. Inner margin of pectoral deeply concave, its inner corner acutely pointed. 



cubensis Howell-Rivero, 1936, p. 473. 

 2b. Inner margin of pectoral only very weakly concave, its inner corner approxi- 

 mately a right angle. 



3a. Second dorsal spine reaches to apex of fin (Fig. 87 I) ; horizontal diameter 

 of eye longer than distance between nostrils, and nearly % (60%) as long as 

 snout in front of mouth. blainville RIsso, 1826. 



Mediterranean, Canaries, 

 Portugal, Black Sea. 

 3b. Second dorsal spine reaches only about % the way to apex of fin (Fig. 87 E) ; 

 horizontal diameter of eye a little shorter than distance between nostrils, and 

 less than V2 (40%) as long as snout in front of mouth. 



jernandinus Molina, 1782, p. 478. 



Squalus acanthias L,innztus, 1758 



Spiny Dogfish, Piked Dogfish 



Figures 87 A-D, 88 



Study Material. About 1 20 preserved specimens, of all sizes, from embryos and new- 

 born to large adults, from various localities along the New England coast and Newport 

 News, Virginia, in the western Atlantic," from Bohuslan, Sweden, North Sea and Mediter- 

 ranean in the eastern Atlantic, and from Siberia, Gulf of Georgia, Puget Sound and Cali- 

 fornia in the North Pacific (Harv. Mus. Comp. Zool.); also many specimens, fresh- 



23. Including a female, 272 mm. long, from Cuba, with umbilical scar still visible, the type specimen of S. barbouri 

 Howell-Rivero, 1936. 



