SILUBIDJE. 121 



wide, the gill-membranes not being confluent with the skin of the 

 isthmus, but notched nearly to the chin. Mouth terminal and 

 transverse ; jaws of about equal length, or the lower the longer. 

 Nostrils remote from one another, the posterior provided with a 

 barbel. Barbels eight. Eyes small. Villifonn teeth in the jaws 

 and on the palate. First dorsal fin without a spine, and with from 

 six to eight rays ; adipose dorsal long and low. Anal of moderate 

 length (15 to 23 rays); ventrals inserted below the dorsal and 

 with five or six rays ; caudal lanceolate or rounded. Air-bladder 

 not enclosed in bone. Skin smooth. 



Gill subdivided the genus into those species which have the 

 jaws subequal in length, the anal with more than 20 rays, and the 

 caudal lanceolate (Olyra) ; and those in which the lower jaw 

 projects, the anal has less than 20 rays, and the caudal is rounded 

 (Branchiosteits). 



Geographical Distribution. Small fishes from the Khasi hills and 

 British Burma. 



Synopsis of Indian Species. 



D. 7/0, A. 18-23. Jaws of equal length. Cau- 

 dal lanceolate 1. O. longicaudata, p. 121. 



D. 8/0, A. 16. Jaws of equal length. Caudal 



lanceolate 2. O. burmanica, p. 121. 



D. 6/0, A. 15. Lower jaw the longer. Caudal 



rounded 3. 0. laticeps, p. 122. 



128. (1.) Olyra longicaudata, 



Olyra longicaudata, McClelland. Calc. Jour. N. H. ii, p. 588, pi. xxi, 

 fig. 1 ; Day, Fish. India, p. 475, and Supplement, p. 800 (see synon.), 



B. vi. D. 7/0. P. 1/4. V. 5. A. 18-23. C. 12. 



Length of head 7, height of body 14 in the total length. Eyes 

 behind the angle of the mouth and above its level, small, the 

 diameter of each equal to half the length of the snout ; they are 

 two diameters apart. Barbels eight, the maxillary reaching the 

 base of the pectoral fin, the remainder short. Fins rayed dorsal 

 as high as the body, the adipose very low. Pectoral spine strong 

 and serrated, the fin being as long as the ventral, the latter arises 

 below the commencement of the dorsal and nearer the vent than 

 the gill-opening. Anal scarcely so high as the body above it. 

 Caudal lanceolate, its upper rays being prolonged. 



Hob. A small species obtained from the Khasi hills and Tenas- 

 serim. 



129. (2.) Olyra burmanica. (Fig. 51.) 

 Olyra burmanica, Day ; Fish. India, p. 475, pi. cxi, fig. 5. 

 D. 8/0. P. 1/4. V. 7. A. 16 (3/13). C. 17. 

 Length of head 7^, of caudal fin 3, height of body 74 in the total 

 length. Eyes small, subcutaneous, and in the anterior half of 



