295 
equal to length of pectorals, which are much less than '/, 
length of head; their flattened spine, serrated behind, less 
than '/, length of head and much shorter than that of dorsal. 
Ventrals rounded, not reaching anal and about ?/, of length 
of head. Caudal deeply forked. Axillary pore present. Villi- 
form teeth in a broad, rounded band in the upper jaw, in two 
_ separate narrower bands in the mandibles. On the palate in 4 
Fig. 120. Arius nudidens M. Web. X 0.3. 
patches, the 2 rounded median ones half their diameter apart, 
touching the oval lateral ones, the long axes of which diverge 
posteriorly. ro stiff, triangular, flattened gillrakers, the longest 
longer than branchial filaments. Whitish silvery, upperpart of 
head and body dark-bluish. Fins hyaline. Margin of dorsal, 
caudal and anterior part of anal blackish. Length 487 mm. 
Habitat: South New Guinea (Lorentz river!). 
In fresh water. 
