OCR Text |
Show 708 SURGEON F. DAY ON THE [Dec. 5, the Punjaub and Burmah. Arius manillensis, Cuv. et Val., may, however, belong to the genus, although, as its specific name implies, it is stated to have come from Manilla. Genus ARIUS. In the species of this genus which I have examined the air-vessel is enclosed in bone; but a short time since the following remark by Dr. Taylor of Dacca, published in the ' Gleanings in Science' (vol. ii. 1830), made me desirous to obtain __. gagora before I completed this paper; this I have now accomplished. Dr. Taylor observes, " in the Pimelodus gagora there are two air-vessels, lodged one on each side in an osseous cup, attached by a narrow neck to the body of the first vertebra, close to its junction with the cranium." He goes on to describe what he found; but it could not have been in Arius gagora, H. B. In Owen's 'Comparative Anatomy' (vol. i. p. 491) it is stated of the air-bladder of fishes that it is "seldom divided lengthwise into two bladders (Arius gagora, Polypterus, Lepidosiren, fig. 324)." ARIUS GAGORA, Ham. Buch. pl. 10. f. 54. Air-vessel large and somewhat heart-shaped, with a moderately thick external fibrous coat. On removing its front wall a longitudinal partition becomes apparent, but is not extended to its anterior portion. It has three transverse subdivisions, forming it into five cavities, owing to the longitudinal partition commencing at the first transverse subdivision. These lateral cavities freely communicate with one another on the same side, and with the opposite ones by means of the anterior chamber, which does not possess any subdivision. This is the only species of the genus which I have found in fresh water high up rivers, having taken it at Mandalay in Native Burmah, about 650 miles from the sea. ARIUS JATIUS. Pimelodus jatius, H . B. Amongst many specimens that I have obtained in Calcutta this year the anal rays were nineteen or twenty; and I can indorse Hamilton Buchanan's and Mr. Blyth's observations as to the difficultv of seeing the granular palatine teeth. I believe, from the description, that A. macracanthus, Giinther, reputed to have been obtained from Siam, is this species. ARIUS SONA. Pimelodus sona, H. B., appears to be the Bagrus gagorides, Cuv. Ct V ill. ARIUS NENGA. Pimelodus nenga, H. B. (MS. figure), appears to be the Bagrus anoides, Cuv. et Val. v |