AEIUS. 



385 



1. ARIUS LATISCUTATUS. 



Arius latiscutatus, part., Gilnrh. Cat. Fish. v. p. 151 (1864) ; Bouleng. Poiss. Bass. 



Congo, p. 300 (1901). 

 Arius parkii, part., Giintli. t. c. p. 154. 



Depth of body 4 to 5 times in total length, length of head 3-^ to 4 

 times. Head slightly longer than broad, the posterior part of its upper 

 surface rough with pearl-like granules; occipital process tectiform, 

 broader at base than long, in contact with the interneural shield, which 

 is small and crescentic and studded with granules same as on the skull ; 

 snout broad, rounded, projecting feebly beyond mouth; eye lateral, 

 oval, 1^ (young) to 2^ times in length of snout, 4-^ to 8 times in length 

 of head, 2\ to 5 times in interocular width ; prsemaxillary band of teeth 



Fig. 297. 



Arius latiscutatus. 

 Cameroon. \. 



5 to 6 times as long as broad ; palate with two very large groups of 

 villiform teeth, consisting of an anterior transverse portion narrowly 

 separated from its fellow on the median line and a posterior triangular 

 portion which is longer than broad ; maxillary barbel § to -|- (1| in the 

 young) length of head, outer mandibular i to f (or once), inner 

 mandibular f to f. Gill-rakers moderately long. 12 or 13 on lower 

 part of anterior arch. Dorsal I 7, spine f to -f length of head, with 

 granular tubercles anteriorly and small serraB posteriorly. Adipose 

 dorsal small, its base at least -| that of rayed dorsal, about twice as 

 distant from latter as from caudal. Anal 19-20 (13-14 rays branched). 

 vol. n. 2 o 



