1 62 THE TANGANYIKA PROBLEM. 



15. Clarias liocephalus. — Blgr. 



Vomerine teeth in a narrow band, without posterior process. Depth of body, 5^ 

 times in total length ; length of head, 5 \ times. Head smooth, covered with soft 

 skin, slightly longer than broad ; occipital process very short, angular ; diameter 

 of eye, 3 times in length of snout, 6 times in interorbital width ; maxillary barbel 

 as long as the head, nasal barbel a little shorter ; inner mandibular barbel \ length 

 of head. Dorsal 70. Anal 50. Caudal free. Pectoral h length of head, not 

 extending to the vertical of origin of dorsal fin. Uniform blackish brown. 



Total length, 80 millim. 



Described from a single specimen from Kinyamkolo. 



16. Chrysichthys cranchii. — Leach, 18 10. 



17. Chrysichthys myriodon. — Blgr. 1900. 



Depth of body, 4.} times in total length ; length of head, 33 to 3J times. Head 

 broad and much depressed, \ longer than broad, rough on the vertex and occiput ; 

 snout broadly rounded, scarcely projecting beyond the lower jaw, \ length of head 

 and twice the diameter of the eye, which is contained 6 times in the length of head 

 and 2 to 2k times in the interocular width ; the occipital process, which is rough 

 like the occiput, in contact with the interspinous shield ; nasal barbel, ij 1 2 i the 

 diameter of the eye ; maxillary barbel a little more than half the length of the 

 head ; inner mandibular barbel, 5 length of the head, outer a little less than half. 

 Vomero-pterygoid teeth very fine and closely set, as are also the preemaxillary and 

 mandibular teeth, forming a broad, horseshoe-shaped, uninterrupted band ; its width 

 in the middle a little less than that of the praemaxillary band, but increasing at the 

 sides, where it much exceeds the latter. Dorsal I. 6 ; spine, rugose, not serrated, 

 nearly half the length of the head and , to f the length of the longest soft rays. 

 Adipose dorsal, a little longer than deep, its base § that of the rayed dorsal and & 

 the distance which separates it from the latter. Anal IV. 8-9. Pectoral spine a 

 little longer and stronger than the dorsal, feebly striated, and bearing on its inner 

 edge about twenty strong retrorse serras. Ventral not reaching the anal. Caudal 

 deeply notched, with obtusely-pointed lobes, the longest rays measuring double the 

 length of the median. Caudal peduncle i| to twice as long as deep. Olive-brown 

 above, white beneath. 



Total length, 470 millim. 



This description is taken from three large specimens, one received from Albertville 

 by the Congo Museum, through Captain Hecq, one from Tembwi, and one from 

 Kinyamkolo, obtained during the second Tanganyika expedition. Compared with 

 specimens of C. cranchii of similar size, C. myriodon differs by its smaller and more 

 numerous teeth, the greater posterior width of the vomero-pterygoid band, the larger 

 eye and the more strongly serrated pectoral spine. It has also a higher number of 

 vertebrae (20-27). 



Z2 



Some young specimens, measuring up to 130 millim., collected at Kibwesi, in 



