305 



stiff gillrakers, :< / 4 of branchial filaments, about half eye. Length 

 about 370 mm. 



Habitat: New Guinea (Lorentz river!, Moaif river! 

 Kaiserin-Augusta river !) ; Aru-islands ! 



In rivers. 



21. Arius melanochir Blkr. 



Arius melanochir Bleeker, Nat. Tijdschr. Ned. Ind. III. 1852, p. 590. 

 Cephalocassis melanochir Bleeker, Ichth. Arch. Ind. Prodr. I. Siluri, 1858, p. 103. 



Atl. Ichth. II. 1862, p. 30. 

 Arius melanochir Gunther, Cat. Brit. Mus. V. 1864, p. 161. 



B. 6; D. I. 7; A. 1719; P. I. 11 12; V. 6. 



Elongate; height (measured below dorsal spine) 5 ] / 4 , head 

 4 or more than 4, the height and the width of the head are 

 subequal and about equal to its length without snout. Bones 

 on the crown of the head rugous; occipital process narrow, 

 much longer than the width of its base, its sideborders nearly 

 parallel, its truncate hindborder touches the narrow basal 

 bone of the dorsal spine. Dilated, heartshaped median fontanel 

 on the occiput, on both sides of which a lateral oval fontanel. 

 Eye 6 8, with an incomplete superficial free orbital margin, 

 situated in the anterior half of the head, more than twice in 

 the length of the snout and in the 

 interorbital space. Dorsal profile slightly 

 convex, sloping to the conical, bluntly 

 rounded, prominent snout. Maxillary 

 barbels extending on pectorals, the 

 mandibulary ones to the base of the Fig I30 AHns 1} ~ lanochlr 

 pectorals, the mental ones to the hind- Blkr. Teeth of upper jaw and 

 border of the gillmembrane. Height of P alate X 2. 

 dorsal as long as head or somewhat shorter, its strong, flattened 

 spine somewhat shorter, its frontborder granulated and serrated 

 at its top, the hindborder with the dentations partly directed 

 upward. Base of adipose fin much longer than that of anal 

 and dorsal, less than i'/ 2 in its distance from it. Its origin 

 far before origin of anal. Height of concave anal equal to the 

 ventrals, which don't extend to its origin. Pectorals scarcely 

 shorter than head, with a very strong, flattened spine, serrated 

 at both sides, which is slightly shorter than that of the dorsal. 

 Small, conical teeth in the jaws and in two widely separate, 

 oblique, posteriorly diverging, more or less elliptic patches on 

 INDO-AUSTRALIAN FISHES II. 20 



