I860.] Tlie Cartilaginous "Elsies of Lower Bengal. 45 



ginatus, Tb. imbbicattts, Te. walga, Te. Bleekeei, Te. Ellioti, 

 Te. Russellii, Te. uaenak, and Te. vaeiegatus ; besides Htpo- 



LOPHTJS SEPHEN, AeTOBATIS FLAGELLUM, RhINOBAXUS GRANTJLATUS, 



Sphtenias Blochei, Peistis antiquorum and Pe. pectinatus, 

 and Sqttalus Milbeeti (?), Sq. gangeticus, and Sq. Temminckii ; 

 — in all seventeen species of cartilaginous fishes. 



I add a brief notice of a young Trygon which I cannot find to 

 be described, obtained on the Arakan coast, and now in the Medical 

 College Museum of Calcutta. 



Te. Ceoziebi, nobis, n. s. Tail twice as long as the disk, com- 

 pressed, with a considerable membrane on more than half the length 

 of its inferior surface, commencing below the insertion of the spine, 

 being nowhere however so high or deep as the tail itself. United 

 pectorals much prolonged into an acute peak anteriorly. Disk 

 smooth, with a mesial dorsal line of tubercles, beginning a little 

 behind the head, where a line of 11 (the last of them increasing in 

 size) have made their appearance above the surface ; the rest are 

 narrower and below the surface of the skin to the base of tail, where 

 a series often very stout prickles or decumbent spinelets — compressed 

 and pointing backwards and forming a range like the teeth of a saw, 

 — is continued nearly to the base of the caudal spine ; the latter 

 being much as in other Trygons, and having a backward-directed 

 serrature on each side for its terminal third. The colouring appears 

 to have been pale above, but no markings are discernible in the dry 

 specimen. Length of disk 11 in. and breadth the same ; tail 23 in. 

 This Teygon has the appearance of being the young of a very large 

 species. Anterior to the range of 11 developed caudal spinelets, two 

 others can be distinguished of equally large size within the skin, and 

 anterior to these the series consists of much smaller and narrow 

 spinelets, until again the size is abruptly greater a little anterior to 

 the centre of the disk. 



April 2nd, 1S59. 



