338 



mouth is closed. Jaws about equal, with a narrow band of 

 small fixed conical teeth, palate toothless. Scales ctenoid, 

 regularly arranged, large, 29 — 33 in a longitudinal series. Lateral 

 line interrupted below middle of dorsal fin and continued lower 

 down. Dorsal with 14 — 19 spines and 8 — ii rays, originating 

 in advance of the anal, which has 14 — 17 spines and 10—13 

 rays. Soft dorsal and anal prolonged, pointed, scaly at the 

 base and their rays branched. Caudal" elongate, terminating 

 in an obtuse point. Pectorals rounded ; ventrals inserted below 

 their base, with a spine and 5 rays, the first of which is pro- 

 duced into two filaments. Operculum without serrature, prae- 

 operculum denticulated. Branchial arches with toothed tubercles. 

 Distribution: Fresh water fishes of Ceylon, Singapore, 

 Sumatra, Java and Borneo. 



I. Polyacanthus hasselti C.V. (Fig. 87, pag. ^t,'/). 



Polyacanthiis hasselii Cuvier & Valenciennes, Hist. nat. Poissons VII. 1831, p. 353- 

 Polyacanihiis Knhlii Bleaker, Nat. & Geneesk. Arch. Ned. Indie II. 1845, p. 520 



(nom. tant.). 

 Polyacantlius Hasselti Bleeker, Verh. Bat. Gen. XXllI. 1850, Vissch. Doolhofv. 



kieuw., p. 9. 

 Polyacanthus Einthovenii Bleeker, Nat. Tijdschr. Ned. Ind. II. 1851. p. 423. 

 Polyacanthus Helfrichii Bleeker, ibid. VIII. 1855, p. 162. 

 Polyacanthus hasselii Giinther, Cat. Brit. Mus. III. 1859 — 1861, p. 378. 

 Polyacanthus Hasseltii Bleeker, Atl. ichtli. IX. 1877, tab. 396, Osphrom. tab.II. fig. 7. 

 Polyacanthus Hasseltii Bleeker, Verh. Akad. Amsterdam XI^- 1879, Mem. Poiss. 



pharyng. labyrinth, p. 12. 

 Polyacantlius Hasseltii Vaillant, Nouv. Arch. Mus. Hist. Nat. (4) V. 1893, p. 102. 

 Polyacanthus hasseltii Regan, Proc. Zool. Soc. London 1909, p. 772. 



D. XVI— XIX. 10— 13; A. XV— XVII. II — 13; P. 2. II — 12; 



V.I. 5; L.l. 31 — 33; L.tr. ca. -^ 



Height in adult about 2.5, 3.5 in length with caudal. Head 

 somewhat obtuse, ■^.'/ and 4.7 in same lengths. Eye more or 

 less than 4 times in head, nearly equal to snout, which is 

 strongly convex as also interorbital space, the width of which 

 is more than '/.^ the length of the head. Cleft of mouth reaches 

 to vertical from between nostrils. Praeorbital not or only 

 slightly serrated. Praeoperculum more or less denticulated in 

 its lower half. Soft dorsal and anal and filaments of ventrals 

 less produced in young specimens. Dark olivaceous, somewhat 

 lighter below, in young sometimes with dark transverse bands; 

 soft dorsal sometimes with a diffuse blackish spot at its base. 



