18/1.] FRESHWATER SILUROIDS OF INDIA. 707 



Eyes of moderate size, situated nearer the snout than the poste- 

 rior half of the head. 



Width of head equals its height, and is as long as the head with- 

 out the snout. Groove on the summit of the head lanceolate in its 

 posterior half and extending to the base of the occipital process, 

 which is twice as loug as wide at its base, and reaches the basal bone, 

 which is V-shaped. Nasal barbels extend to the posterior margin of 

 the orbit, the maxillary to the middle or end of the pectoral fin, the 

 external mandibular are as long as the head, the internal shorter. 



Teeth in an uninterrupted crescentic band on the palate. 



Fins. Dorsal spine smooth, as long as the head without the snout, 

 whilst the fin is as high as the body below it ; adipose fin small, its 

 base shorter than that of the first dorsal. Pectoral spine as long as 

 the head without the snout ; it is strongly serrated internally. Cau- 

 dal deeply lobed, the upper slightly the longest. 



Colours. Golden, with three or four longitudinal bands formed of 

 black spots in the upper one along the back, and black stars in the 

 lower ones. A darkish blotch formed of spots over the base of the 

 pectoral fin ; some spots on the dorsal and the margins of the other 

 fins stained. 



Hab. Assam and the Punjaub : attaining about 3 inches in length. 



Hamilton Buchanan observes, all the barbels are shorter than the 

 head ; but my specimens so exactly resemble his figure and descrip- 

 tion, except in the maxillary barbels being longer (and they varied 

 in individuals), that I consider they must be the same. I took 

 upwards of twenty in a tank near Goordaspoor in the Punjaub. 



This genus, containing mostly only inhabitants of fresh waters, 

 still has estuary or marine representatives (M. gulio, H. B.). It is 

 found generally throughout India and Burmah, down to the Malay 

 archipelago. 



Rita crucigera, Owen. 



Pimelodus rita, Ham. Buch. pi. 24. f. 53. 



I have found this species throughout the extent of the Ganges and 

 Jumna, and also in the Punjaub rivers ; but it is subject to consider- 

 able variation, due to age and locality. The dorsal spine may be as 

 long as, or longer than, the head, the pectoral being somewhat 

 shorter, whilst the humeral process, although not pointed, is but 

 Tery slightly rounded. 



Air-vessel with a thick outer coat and thin lining membrane. Its 

 external form is somewhat quadrangular ; and posteriorly it is conti- 

 nued into two horn-like processes, nearly or as long as the abdominal 

 cavity ; the right one usually passing over to the left side and curving 

 across the commencement of the left one, whilst the left one first 

 passes downwards and then is sometimes recurved on itself. On the 

 front wall being removed a longitudinal median partition is seen in 

 its posterior half, dividing it into two large smooth cavities, which 

 anteriorly communicate, and are continued posteriorly down the horn- 

 like or tubular processes. 



This genus extends throughout the larger rivers of India and 



