1860.] The Cartilaginous Fislies of Lower JBengal. 39 



adults it is weaker and more greyish, and in them it is also rough. 

 ened wifch minute limpet-shaped tubercles ; these appear again about 

 the gill-openings, and more sparingly medially, and a few are scattered 

 over the entire lower surface, whicb are more readily detected by the 

 feel than by the sight in the fresh specimen. From between the 

 eyes to the sides of the tail, and traceable along two-thirds of that 

 organ, are a couple of series of vermiculated lines ; and there is a 

 double series of the same along the midclle of the back. In a young 

 female, measuring 18 in. to base of tail, with greatest breadth of disk 

 20^- in., and tail 29 in., the tubercles generally are less crowded than 

 in the adult, especially on the tail, where there is little indication of 

 their future development. Although the caudal spine had been 

 broken away in every specimen examined, yet from the groove which 

 it occupied, that of an adult is shewn to be 7i in. long.* It is by 

 no means a rare species, though seldom to be obtained perfect in the 

 fish-bazars. 



Te. ateocissimtjs, nobis, n. s. We have in the rauseum a portion 

 of the tail, above 4 ft. in length, of an enormous Trygon, which is 

 evidently a second species ofthis particular sub-group. The site of 

 the caudal spine is conspicuous as usual, indicating a much stouter 

 but not so long a weapon as that of Tu. marginatus. The limpet- 

 shaped tubercles are very much larger and fewer in number than in the 

 other, each being much expanded at base and abruptly rising to a sharp 

 point in the centre ; they are of diíferent sizes intermixed, and here and 

 there two or more of them are blended at base, and the tail appears to 

 be naturally much compressed. Below the spine, it is naked under- 

 neath along the middle, and beyond the spine this medial portion of 

 the tail underneath is studded with small tubercles. "Where broken 

 off, at a distance of 4¡ ft. from the spine, it seems to expand vertically, 

 being there twice as deep as broad. It is a truly frightful and most 



* The Medical College specimen has a perfect caudal spine. It is larger than. 

 the young example above described, with tail about 40 in., and spine 2f in. ; 

 some small sharp tubercles around the base of the latter. The dorsal tubercles 

 are smaller than in the other ; those on the base of the tail more crowded. Sex 

 male, that of the other female. The mai'ginal band of the lower surface is repre- 

 sented only by a few distantly scattered spots. 



