Dr. A. Giinther on a new Lahyrinthihranehiate Fish. 211 



heliciform Vertigo and by a large Succinea, also taken by Mr. 

 Blanford, who will probably describe them together with a large 

 Helix allied to H. BajaderUy Pfr. 

 Cheltenham, Feb, 5, 1864. 



XXIV. — Description of a Lahyrinthihranehiate Fish from the Nile, 

 By Dr. Albert Gunther. 



A VERY fine collection of fishes made on the Upper Nile, 

 at Chartoum and Gondokoro, by Consul John Petherick, con- 

 tained, among other novelties, a species of Labyrinthibranchiate 

 fish belonging to the genus Ctenopoma, Peters, species of which 

 have hitherto been found only in Southern and Eastern Africa, 

 where they represent the East-Indian Anahas, 



Ctenopoma Petherici. 



D. jj, or f, or ^\ A. ^,-,. L. lat. 29. L. transv. '-^*. 



The height of the body is one-third, or a little more than 

 one-third, of the total length (without caudal) ; the maxillary 

 extends to below, or but slightly beyond, the anterior margin of 

 the eye. Teeth in the jaws and on the palate in narrow bands. 

 The diameter of the eye equals the extent of the snout. Five 

 series of scales between the orbit and the angle of the prse- 

 operculum, the outer series covering the prseopercular margin. 

 Operculum, inter-, and suboperculum strongly serrated. The 

 soft rays of the vertical fins covered with small scales. Brownish 

 olive j many scales with a brown central spot, these spots being 

 less distinct in old specimens than in young ones; a round 

 black spot, sometimes edged with whitish, on the root of the tail. 



The largest specimen is 6^ inches long. 



This species is more nearly allied to C. multispine than to 

 C. microlepidotum, but may be readily distinguished by its 

 deeper body, by its narrower mouth, the maxillary extending to 

 below the middle of the eye in C. multispine, &c. 



The same collection contained examples of Opkiocephaliu 

 obscurus, Gthr., described from West-African specimens, and a 

 complete series of Clarotes, showing that this genus has been 

 founded by Hyrtl and Kner on a deformed specimen, and that 

 the species has been long ago named Pimelodus laticeps by 

 Riippell, the development of the rays and of the spine of the 

 adipous fin being dependent on age. 



