152 SILURID^. 



snout very broad, obtusely rounded. The teeth are vUliform : the 

 vomerine band is not quite twice as broad 

 as that of the intermaxillaries, and divided 

 into two by a narrow interspace ; each 

 half is about twice as broad as long, and 

 separated from the palatine patch by a 

 linear transverse groove, which disappears 



altogether in old age. The palatine teeth V_-;^ I I ^%>_ 

 form a large triangular patch which is ( ' 



longer than broad ; the patches are broader \ ' ' 



than the space between them. Dorsal and \ / \ / 



pectoral spines strong, serrated along both 

 edges ; the former is a httle the shorter, and as long as the head 

 without snout. Adipose fin short ; caudal deeply forked. 

 West Africa. 



«. Stuffed, 16 inches long. Fernando Po. Purchased of Mr. Stevens. 

 b-c. Skeletons, 52 and 43 inches long. West Africa. Purchased of 

 Mr. Dalton. 



B. Teeth on the palate gi-anidar. 



25. Arius luniscutis. 



Arius luniscutis, Cuv. ^- Veil. xv. p. 109 ; Kner, Sitzgsber. Wien. Acad. 

 1858, xxvi. p. 390. 



D. 1/7. A. 20-21. P. 1/11. Vert. 18/31. 

 The height of the body is one-fifth of the total length (without 

 caudal), the length of the head one-fourth; head depressed, much 

 lower than broad, its greatest width being equal to the distance of 

 the hinder nostril from the end of the opercle. Eyes small, situated 

 in the beginning of the middle third of the length of the head ; 

 interorbital space wider than the snout is long. Teeth on the palate 

 in very broad confluent bands, those of the palatine bones separated 



from each other only by a narrow space ; teeth on the vomer rather 

 obtuse. The maxillary barbels extend to, or nearly to, the end of 

 the head ; the outer mandibulary barbels are half as long as the head. 



