Fishes. 1981 



canicula), or that of the large -spotted dogfish or nurse-hound {Scyl- 

 lium catulus), as represented in Mr. Thompson's figure. But the 

 greater distinction is in the structure of the surface, which in the cases 

 of all the rays that I have examined, is smooth or plain, with a lon- 

 gitudinal direction of the fibre. In the present instance this structure 

 is peculiar and beautiful ; the surface being thickly set with raised lon- 

 gitudinal lines, closely crossed with dots or raised lines ; — that is, each 

 longitudinal line is very thickly studded with raised marks, points or 

 short lines, which do not pass from one longitudinal line to another, 

 but sink into the minute channels between them. This description, 

 however, applies only to the middle of the surface, for towards 

 the ends and sides the longitudinal lines become thus joined ; and 

 the reticulations form fine and beautiful squares, which are still finer 

 on the border; and on the extreme margin they disappear. The 

 colour, when I received it, was very dark, but browner at the bor- 

 ders. There were a few small Serpulae and Flustrae attached to the 

 surface. 



It was a considerable time, after I obtained this case, when I 

 became aware that at the time it was found, it contained an embryo, 

 which on my further inquiry was kindly submitted to my examination. 

 The ovum or yolk, which had been immersed in a bottle of Mr. 

 Goadby's preserving fluid, was as large as an ordinary orange, but 

 somewhat compressed: the foetus comparatively small, and conse- 

 quently far from being fully developed. The mouth was placed far 

 under a projecting snout, which rose into an elevated vertex. The 

 eyes large, projecting laterally from the sides of the head. The 

 head distinct, joined to the body by a neck. Pectoral fins with 

 a shoulder, as in the genus Squatina ; the anterior angle advancing 

 near to the eyes ; their outer margin a little sloped, and passing- 

 backward in a direction corresponding with the outline of the body. 

 Ventral fins small and slender. The situation of the branchiae is well 

 marked dorsally, with fixe lines, showing the number of orifices ; 

 branchial fibres long, as in the early state of other embryotic chon- 

 dropterygious fishes. 



The body is narrow, with a dorsal ridge that runs down the caudal 

 portion to the end ; and at a third of its length from the body this 

 ridge begins to be bordered, as with a narrow fin, that seems to 

 decrease again as it proceeds. This caudal portion has also a ridge 

 beneath, which begins close to the vent ; and on both sides there is 

 a membranous border. The tail is long and narrow, tapering, but 

 without an obvious fin towards the end. 



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