85. JiocHOCTJS. 217 



the anterior margin of the mandible, the outer ones extending to 

 the root of the ventrals, the inner ones being somewhat shorter, and 

 pro\-i(led ^\•ith two or three additional filaments. The entire neck is 

 (uirassed, the enirass being composed of three transverse pieces ; the 



lateral margins of the nuchal cuirass are nearly parallel. Humerus 

 with a long, slender process, which extends nearly as far backwards 

 as the nuchal shield. Dorsal spine slightly serrated in front and as 

 long as the head ; the pectoral spine is strongly serrated interiorly, 

 stronger and longer than that of the dorsal fin, and extending beyond 

 the root of the ventral. The second dorsal fin has a rounded upper 

 margin, commencing before and tenuinating behind the anal. Caudal 

 forked. Body immaculate. 

 Upper Nile. 



(I. One and a half inch long. Gondokoro. From Consul Petherick's 

 Collection. 



A genus which appears to be closely allied to lihinoijJanis has been 

 discovered by M. de Joannis. Unfortunately, Valenciennes has not 

 taken any notice of it, so that we are obliged to give an abstract from 

 the notes published by the collector. 



85. MOCHOCUS. 

 Mocliokus, Joannis, Gticr. Mat/. Zool. 1835. 

 Two dorsal fins, both composed of rays, the first with a strong spine ; 

 anal short. Teeth in the upper jaw only, in a single series. Mouth 

 of moderate vrn\i\\ ; barbels six, thin. Eyes of moderate size. Neck 

 covered \\\{h soft skin. GiU-openings rather narrow. Ventrals six- 

 rayed, inserted innuediately behind the dorsal. 

 Nile. 



1 . Mochocus niloticus. 



Joannis, I. c. pi. 8. 



D. i- 1 1(1. A. 8. P. 1/3. V. 6. 



The length of the head is two-ninths of the total (^^athout caudal). 

 Barbels subecjual in length, scarcely longer than the head. Dorsal 

 spine longer than the head, but only two-thirds as long as the spine 

 of the ])ectoral fin, which is exceedingly strong. Head, body, the 

 second dorsal, and the caudal with browuisli-ldack spots. {Jomuiit:.) 



Nile, near Thebes. 



Onlv 1"^ lines loiii;-. 



