894 SQUALIDiE. 



any other British Shark as to serve the purpose of a distin- 

 guishing character. The peculiarity in the form and arrange- 

 ment of these teeth, so closely resembling those of the Skate, 

 is seen by comparing the vignette before referred to with that 

 representing the teeth of the Thornback, which is given 

 hereafter, when describing the first species of true Skate. 



The young of the Smooth Hound frequently have nume- 

 rous small white spots above the lateral line ; but the teeth 

 and other characters agree so closely with the spotless grey 

 examples of larger size, that I am induced to consider these 

 spots only as marks of youth, which may also be observed in 

 other species, particularly in the Picked Dog-fish, Spinax 

 Acanthias, Cuvier : and in this view I am further confirmed 

 by the opinions of Mr. Couch and Dr. Johnston. 



Mr. Couch says of this species, in reference to its habits, 

 that it is common, but not abundant, and keeps close to the 

 bottom on clean ground, where it feeds on crustaceous ani- 

 mals, which it crushes previous to swallowing, and for which 

 its flat pavement-like teeth are well adapted : it also takes a 

 bait, but is less rapacious than most of the tribe. The young 

 are produced alive in November, the whole coming to perfec- 

 tion at once ; but they are few in number, not perhaps ex- 

 ceeding a dozen, and soon after birth they all go into deep 

 water, from which they do not emerge until the following 

 May. 



This species has been taken on the coasts of the counties 

 of Antrim and Londonderry. 



The specimen described measured eighteen inches in 

 length ; the top of the head flat and rather broad ; the begin- 

 ning of the back elevated and rather rounded ; the eye large, 

 lateral, elongated horizontally ; temporal orifices rather small, 

 and placed immediately behind the posterior angle : first dorsal 

 fin considerably larger than the second ; both of the same 



