18 



PRISTIURTJS. 



This genus flifFers from Sc)/nin»i in having a more lengthened snout, 

 nostrils unconnected with the mouth, and by a row of larger reclin- 

 ing spines or scales arranged like a saw along the upper edge of the 

 tail; which latter organ proceeds in a right line with the bodj-, 

 as in ScylUum. The generic name refers to the saw-like structure of 

 the ridge of the tail. 



BLACK-MOUTHED DOGFISH. 



EYED DOGFISH. 



ScijlUiun melanostomum, Yarbell's Br. Fishes, vol. ii., p. 495. 



Prisilunis melanosfomus, Lowe's Fishes of Madeira, T. 14. 



Prist Idurus melanostomus, Gkay; Catalogue Br. Mus., p. 124. 



This fish is widely spread, altliougli it was not recognised 

 as a species — at least in Britain — before the publication of Mr. 

 Yarrell's History of British Fishes; which contained the figure 

 and description, a specimen of which, a larger likeness, is given 

 in this volume. It has since been found by Mr. Lowe, in 

 the Island of Madeira; and it now appears that it is scarcely 

 rare in some parts of the north of our island; where, how- 

 ever, before the publication of an authentic likeness, it had 

 been supposed the same with our Nurse Hound: the last- 

 named species being therefore unknown on that coast. 



The Black-mouthed or Eyed Dogfish is better known in the 

 Mediterranean than with us. It is mentioned by Risso and 

 Uafinesque, but without adding much to our knowledge of its 

 habits. The latter says that the blackness of the inside of its 

 mouth had caused it to have the name — in Italian, of Bocca 

 d'Inferno, or hell's mouth. Its haunts aiJpear to be near the 

 ground, and both the examj^les I have met with were caught 

 with the line. It also resembles its nearest affinities the Scyllia, 

 in depositing egg-cases in which the young are hatched; but 



