46 TOPER. 



I 



young I have met with was thirty-two, but fifty- two have been 

 found. They remain near us in the winter, for I have met 

 with them in January; being then about twenty inches in length, 

 with three rows of teeth; the outer or oldest row of which had 

 only one notch on its edge. At this time the older fishes have 

 left the coast, and perhaps have retired to deeper waters. 



Among ourselves this fish is little regarded as food; but 

 Willoughby found it exposed for sale in the market at Rome; 

 and fishermen inform me that French people freely purchase it 

 for the same purpose. 



It grows to the length of six feet, but is not often found of 

 that size. The shape is somewhat round and slender, especially 

 towards the tail. The snout depressed and lengthened, and 

 diaphanous towards the borders; in fish of full size a narrow 

 fold of skin passes over the eye, but I have not observed it 

 in the young examples. Spiracles small and near the eye. 

 Nostrils small, near the border, and not lobed; mouth far be- 

 neath; teeth triangular, serrated on the posterior or inner edge 

 only; their position alternate in the rows. Gill openings above 

 the origin of the pectoral fins. The first dorsal fin nearer the 

 head than the tail, the second opposite the anal, the pectorals 

 wide near their origin. Upper lobe of the tail notched. Colour 

 a dark ash above, white below. The eye is oval, and the tablet 

 on which the globe of the eye is placed in most, if not all the 

 Sharks, as already mentioned, is less elevated or clearly marked 

 than in the other species with which I am acquainted. There 

 are also some other particulars connected with the eye of this 

 fish, which appear to imply different powers of vision from those 

 of other species of Sharks. The outer coat or capsule of the 

 eye-ball is firm, but it becomes thinner and more yielding at 

 the transparent cornea; which, consequently, when pressed by 

 the director muscles, must become more convex; as we also 

 find in some birds, which thus possess the faculty of adjusting 

 vision to different degrees of distance. The pupil is very small. 

 A nictitant membrane, formed of a doubling of the eyelid, is 

 capable of being raised from the inner angle of the eye, to 

 cover two thirds of the eve-ball. 



