482 Memoir Sears Foundation for Marine Research 



lb. First dorsal spine behind tips of pectorals when latter are laid back. 



3a. Interspace between 2nd dorsal and caudal as long as from eye to origin of pectoral, 

 or longer. 



4a. Second dorsal spine over midbase of pelvics, and extending considerably 

 beyond apex of 2nd dorsal fin; interspace between 2nd dorsal and caudal 

 about as long as from eye to axil of pectoral. ^granulosum Gunther, 1 8 80. 



Falkland Islands.* 



4b. Second dorsal spine posterior to rear ends of bases of pelvics, and extending 

 only V2 to % the distance toward apex of 2nd dorsal; interspace between 

 2nd dorsal and caudal only about as long as from eye to origin of pectoral. 



ritteri Jordan and Fowler, 1903. 



Japan. 



3b. Interspace between 2nd dorsal and caudal only about as long as from eye to ist 

 gill opening. fabrkii Reinhardt, 1825, p. 482. 



Centroscyllium fabricii (Reinhardt), 1825 



Black Dogfish 



Figure 91 



Study Material. Two females, 640 and 727 mm. long, one from the continental slope 

 off Browns Bank, the other from off Nova Scotia in 300 fathoms (Harv. Mus. Comp. 

 Zool., No. 35702 and 743). 



Distinctive Characters. Among West Atlantic members of its family this species falls 

 with Squalus acanthiasy S. cubensis and Etmofterus hillianus in its long and very prominent 

 fin spines. But it is easily separable from the first two by its teeth, which have several cusps, 

 by its dermal denticles, and by its color. It differs most obviously from Etmofterus hil- 

 lianus in that its lower teeth have several cusps like the uppers, and that its second dorsal 

 originates over the bases of the pelvics. 



Description. Proportional dimensions in per cent of total length. Female 640 mm., 

 from 240 miles ESE. of Boston Lightship (Harv. Mus. Comp. Zool., No. 35702). Fe- 

 male, 727 mm., from off Nova Scotia (Harv. Mus. Comp. Zool., No. 743). 



Trunk at origin of fectoral: breadth 1 1.8, 1 1.8 ; height 7.8, 8.2. 



Snout length in front of: outer nostrils 1.4, 1.8 ; mouth 7.5, 7.4. 



Eye: horizontal diameter 4.7, 4.3. 



Mouth: breadth 8.1, 8.2; height 3.3, 3.7. 



Nostrils: distance between inner ends 3.9, 4.2. 



Labial furrow length from angle of mouth: upper 1.9, 2.2; lower 1.9, 1.9. 



Gill opening lengths: ist 3.1, 3.O; 2nd 3.1, 3.0; 3rd 3.1, 3.0; 4th 3.1, 3.0; 5th 



2.7, 2.6. 



4. Diagnosis based on Burckhardt's (Ann. Mag. nat. Hist., [7] 6, 1900: 567, fig. 8) illustration of the type speci- 

 men. 



