3ot 



convex line in young specimens, stronger convex in old speci- 

 mens, with a concavity behind head. Height 2.3 — 3.2, 2.7 — 4 

 in length with caudal. Head 3.4 — 3.9, 4 — 4.8 in length with 

 caudal. Eye 3.5 — 4.1, about 1.5 in snout, which is equal to 

 interorbital space and somewhat less than postorbital part of 

 head. Upper jaw prominent. Mouthopening reaching almost 

 or entirely to vertical through frontborder of eye. Pointed, 

 conical teeth in several rows in the jaws, extending to the 

 lips, which are thickened, especially in their anterior part. A 

 large patch of teeth on vomer, on palatines and on base of 

 tongue. Three to four rows of scales on subocular part of cheeks. 

 Operculum with large scales, excepting the superior ones, 

 which are small. Dorsal separated by 18 — 19 scales from occiput. 

 Spine of first dorsal somewhat shorter than or equal to post- 



Fig. 80. Rhombatiactus lorentzi M. Web. X Vs' 



orbital part of head, much longer or as long as that of second 

 dorsal, which is slightly or much longer than that of anal. 

 Anal spine equal to or longer than eye. Origin of anal about the 

 length of snout in advance of origin of first dorsal. Length of 

 base of anal much longer than distance between origin of first 

 dorsal and end of second dorsal. Pectorals somewhat longer 

 than head without snout. Scales nearly smooth or with faint 

 crenulations along the hindborder. Caudal peduncle as high 

 as long or higher than long. Colour of alcohol specimens light 

 brownish above, silvery white below, sometimes with a partly 

 developed lateral band, which is at least as broad as one scale. 

 Fins somewhat dusky. Length 142 mm. 



Habitat: North New Guinea (rivers Sermowai!, Tawarin ! 

 and Mamberamo'.j. 



