FAMILY, XXXI— RHYNCHOBDELLID^. 339 



In some large specimens from the Kistna there were no ocelli. In others at Moulmein, in Burma, the 

 fish were covered with white spots, the fins reddish, and the dorsal barred. 



Salitat. — Brackish waters within tidal influence, also throughout the deltas of large Indian, Burmese, 

 and Sind rivers, but appears to be absent from the northern portions of the Punjaub and the Malabar coast : it 

 extends to Borneo and the Moluccas : attaining about 15 inches in length. It conceals itself in the mud; and 

 becomes drowned if placed in water so as to be unable to reach the surface, apparently requiring to 

 respire air directly. , 



Genus, 2 — Mastacembelus, Cut. and Val. 



BrcmcMostegals six. Cleft of mouth narrow ; a long fleshy appendage to the snout, which is not transversely 

 striaied inferiorly. Preopercle generally with spinate teeth at its angle : a preorbital spine. Teeth in jaws mirmte. 

 Dorsal and anal fins confluent with, or distinct from, the caudal. Scales small, cycloid. Lateral-line present. 

 Air-vessel elongated. 



A. Vertical flns distinct from the caudal. 



1. Mastacembelus unioolor, D. 83-34 | 81-94, A. 3 | 75-95. Of an uniform brown colour: or covered with 

 large yellow blotches. Burma to Java. 



2. Mastacembelus zebrirms, D. 28-29 | 50-62, A. 3 | 51-56. Yellow with vertical blue stripes: fins 

 striped or spotted. Burma. 



3. Mastacembelus pancalus, D. 24-26 | 30-42, A. 3 | 31-46. Sides spotted with yellowish- white : posterior 

 portion of body more or less banded. Vertical fins with fine black spots. Deltas of large rivers in India and 

 Assam, but not extending to southern India or Burma. 



B. Vertical flns confluent with the caudal. 



4. Mastacembelus armatus, D. 32-39 | 74-90, A. 3 | 75-88. Spinous dorsal commences over middle of 

 pectoral fin, 30 rows of scales between the lateral-line and base of first dorsal ray. Greenish, marbled, spotted, 

 with or without undulating lines. 



5. Mastacembelus OUntheri, D. 27-30 ] 60-74, A. 3 | 62-75. Spinous dorsal commences behind the 

 vertical from the end of the pectoral fin : 15 rows of scales between the lateral-Hne and base of first dorsal ray. 

 Brownish or oUve, marbled and spotted : some dark bands radiate from the eye. Malabar coast. 



1. Mastacembelus unioolor, Plate LXXII, fig. 3. 



(Kuhl and v. Hass.) Cuv. and Yal. viii, p. 463 ; Blocker, Notac. p. 6 ; Giinther, Catal. iii, p. 642. 



B. vi, D. 33-34 I 81-94, P. 27, A. 3 | 75-98, C. 25. 



Length of head 51 of caudal 18, height of body 10^ in the total length. Eyes—l diameter apart. 

 Width of head equals 1/4 of its length, and its height 2^ in its length. Snout with two small tentacles near its 

 extremity. The maxilla reaches to below the front nostril. Three strong denticnlations at angle of 

 the preopercle : a preorbital spine. Fims— dorsal spines short, increasing in length posteriorly, they commence 

 over the middle of the pectoral. Second dorsal and anal divided from the caudal by a deep notch, the latter fin 

 rounded. Second pre-anal spine the longest and strongest. OoZows— brownish superiorly, becommg lighter 

 coloured beneath : three or four rows of oblong, rounded, or irregularly shaped' yellow spots or blotches 

 along the sides: vertical fins with a black yeUow-margined outer edge. Pectorals are said to have two 

 cross-bands. The original specimen was of an uniform colour, hence its name. 



The specimen figured (life-size) was received from Professor Peters, of Berhn. It was captured 

 at Rangoon, and although possessing D. 33 | 94, A. 3 | 98, is evidently Cuv. and Val.'s species. 



Habitat. — Burma to Java. 



2. Mastacembelus zebrinus, Plate LXXII, fig. 3. 



Blyth, J. A. S. of Bengal, 1859, p. 281 ; Gunther, Catal. iii, p. 541 ; Day, Proc. Zool. Soc. 1869, p. 621. 



Nga-ma-way-doh-wettu/ng, Burmese. 



B. vi, D. 28-29 I 60-52, P. 19, A. 3 | 61-56, C. 19. 



Length of head 6 to 7, height of- body 7 to 7| in the total length. Uyes-small situated before 

 the middle of the length of the head. Snout trilobed at its extremity. The greatest width of the head equals 

 1/2 the length of the postorbital portion of the head : its height equals 1/2 its length excluding the snout. Ihe 

 maxilla reaches to below the nostrU. Three strong denticnlations at the angle of the preopercle : a Preorbital 

 spine. Fins— dorsal spines short, increasing in length posteriorly, they commence over the middle ot 

 the pectoral fin. Soft dorsal and anal separated from the caudal by a notch, the last fin rounded. Second 

 pre-anal spine longest and strongest. Scales— 20 rows between the lateral-Une and the commencement ot the 

 soft dorsal fin. Oolours-greejsh along the back, becoming lighter on the sides and beneath, bluish vertical 

 bands, either edged on either side with a golden one, or else the two alternating. Dorsal and caudal 

 fins banded in dots : anal with the body bands continued on to it, and havmg intermediate darJs ones. 



Eabitat.-This species is the common one throughout the fresh waters of Burma, entirely superseding the 

 M. pancalus of Bengal and Assam, it is found in the Irrawaddi, in Upper Burma to iar above Ava. Ihe 

 specimen figured (life-size) is from British Burma. It attains at least 9 mches m length. ^ ^ ^ 



