792 MR. F. DAY ON THE FISHES OF YARKAND. [Dec. 5, 



13. DlPTYCHUS MACULATUS. 



Diptychus maculatus, Steindachner, Verh. z.-b. Ges. Wien, 1866, 

 p. 787; Gtinther, Cat. vii. p. 1/1. 



? Diptychus sewerzowi, Kessler, Fish. Turkestan, p. 17, t. 4. 

 f. 12. 



B.iv., D.g, P. 19, V. 9, A.|, C. 19, L. 1. 80-90. 



Length of head 5 to 6, of caudal 5 to 6, height of body 1\ to 8 

 in the total length. Eyes: diameter Ah in the young to 6 in the 

 adult in the length of the head, 1^ to 2 diameters from the end of 

 snout, and \\ apart. The greatest width of the head equals its 

 height, or its length behind the front edge or middle of the eyes. 

 Mouth transverse, inferior, having an anterior sharp horny covering 

 on the lower jaw. Lower labial fold interrupted in the middle. 

 Barbels : one at each maxilla, having thick bases, and hardly so long 

 as the eye. Teeth pharyngeal, 4, 3.3, 4, curved at the outer ex- 

 tremity and pointed. Fins: the dorsal commences rather nearer the 

 snout than the base of tlie caudal, its upper edge is straight, it is as 

 high as the body below it, its last undivided ray articulated. Pec- 

 toral not quite so long as the head ; it reaches rather above halfway 

 to the ventral, which latter commences on a vertical line below the 

 last dorsal ray ; it reaches rather above halfway to the base of the 

 anal. Anal when laid fiat reaches the base of the caudal, its height 

 is nearly three times the length of its base. Scales : not imbricated, 

 but scattered over the upper two thirds of the body and pectoral 

 region, in which latter locality the skin is often rugose : the tiled row 

 well developed. Free portion of the tail one half longer than high at 

 its base. Colours: bluish, lightest inferiorly, indistinctly blotched 

 and spotted along the upper half of the body, often a narrow, dull 

 band along the lateral line, and a second below it. The dorsal and 

 caudal much spotted in some specimens. 



The very young are destitute of scales ; they first appear along 

 the lateral line. One specimen from Basgo, 1*1 inch long, has 

 no barbel on the left side. There are two specimens from the west 

 of Sirikol : one has an adipose lid, covering the anterior half of the 

 left eye ; the other has a similar lid covering the lower half of the 

 left eye. Brown tubercles are common on some of the specimens, 

 and do not appear to be normal. Some specimens from Leh have 

 the eye small. 



Diptychus sewerzowi, from the rivers Aksai and Ottuck appears 

 to be the above species. 



Hah. Specimens were brought from Kurbu, Basgo, Sneema, Leh 

 or Ladak, Tankse, and Chagra, from waters going directly or indi- 

 rectly to the Indus ; from Pas Robat (9370 feet), and Tarbashi 

 (11,515 feet), where the waters go to the Yarkand river; also from 

 west of Sirikol, which goes to the same river. Some specimens are 

 also labelled as from Chiriscorus. 



This fish has also been captured in other parts of Tibet, and like- 

 wise in Nepal. 



