320 



specimens, in interorbital space. Snout less than twice diameter 

 of eye, its tip in the horizontal through lower half of eye. Cleft 

 of mouth rather oblique. Maxillary reaching far behind eye 

 or to hindborder of eye in small specimens. Lower jaw slightly 

 prominent. A rather broad villiform band of teeth in the inter- 

 maxillaries, teeth coarser in the symphysial part, especially 

 the hindermost. In the lower jaw several rows of teeth near 

 the symphysis, laterally only one row, behind which equi- 

 distant strong canines. A A-formed patch of moderate strong 

 teeth on vomer and an elongate band of strong teeth on the 

 palatines, the innermost row the largest and caninoid. All the 

 teeth curved backwards. There are 5 or 6 scales in a row 

 between the eye and the hindborder of the praeoperculum 

 and 3 — 4 rows on the operculum. Lateral line with an abrupt 

 curve downwards of 3 scales at about the 14th or 15^'^ perfo-' 

 rated scale. Dorsal beginning behind base of pectorals and 

 ending somewhat behind end of anal. Its origin separated by 

 15 — 16 scales from tip of snout. Origin of anal below 14th 

 dorsal ray. Pectorals about as long as postorbital part of head. 

 Ventrals originating about below origin of dorsal, about equal 

 to distance between hindborder of eye and hindborder of 

 praeoperculum. Colour of alcohol specimens dark greenish or 

 bluish above, yellowish or reddish brown below. A rather in- 

 conspicuous dark oblique stripe behind corner of mouth. Under- 

 parts of head sometimes with yellow spots. Pectorals and dorsal 

 and caudal dark, ventrals of the colour of the lower parts, 

 sometimes striped in their hinderpart. Anal light, with a sub- 

 terminal dark band. In young specimens (always?) a red lateral 

 band from snout to caudal. Length 285 mm. [Type of 0. fiara- 

 mensis Steind. in the Vienna Museum seen by us]. 



Habitat: Sumatra (Palembang, Lahat, Gunung Sahilan!, 

 Ringgat!, Laut Tador, Lower Langkat); Banka; Borneo (Ma- 

 rawang, Toboali, uppercourse of river Kapuas, Sadong, Gambas, 

 Sarawak, Baram river!). — Palawan Archipelago, Tonkin, Siam. 



Note. OpJiiocepliahis rJiodotaenia is based on a single specimen 

 of 59 mm. long. A second one, still smaller (41 mm.) has 

 been recorded by Steindachner. The difterences from 0. inela- 

 nosoma (the presence of a lateral red band and the maxillaries 

 reaching only below hinderpart of eye) are referable to the 

 young age of the specimens. We unite O. rhodotaenia there- 

 fore with 0. vielanosoma. 



