DESCRIPTION OF SPECIES. 



PLAGIOSTOMATA. 



SELACHOIDEI— SHARKS. 

 Family Scylliid.e. 



Scyllium, M. and H. 



The species of " Dog-fishes " hitherto known are strictly littoral, and, besides, have 

 but a limited distribution. It is therefore a matter of some interest to find a species 

 living at so great a depth as 400 fathoms, although there is nothing in its organisation 

 which would have led us to suspect its bathybial habits. 



Sci/Uium canescens (PI. I. fig. A). 



Sajllium canescens, Giinth., Ann. and Mag. Nat. Hist., ser. 5, vol. ii. p. 18, 1878. 



The nasal valves are separate from each other, the distance between them being less 

 than the length of a nasal opening ; each is provided with a cirrus. Lengtli of the 

 prgeoral portion of the snout much less than its width, or than the width of the mouth. 

 Labial fold very short. Teeth very small, those of the lower jaw tricuspid, the cusps 

 being subequal in length. Ventral fin with the posterior margin very oblique. The 

 posterior dorsal slightly longer than the anterior. The anal terminates below the middle 

 of the second dorsal, its base being longer than that of the latter fin, and equal to its 

 distance from the caudal. The whole body rough from small spines. Uniform greyish ; 

 all the fins, except the caudal, tipped with white behind. 



Habitat. — South-western coast of South America, Station 310 ; depth, 400 fathoms. 

 One specimen, 11 inches long (young female). 



(ZOOL. CHALL. EXP. PART LVII. 1886.) LU 1 



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