460 DR JOHN ALEXANDER SMITH ON CALAMOICHTHYS, 



wriggling, or struggling movements of the fish, as it propels itself through the 

 water or mud of the river * 



On examining the specimens of these fish, sent to me from Old Calabar, it 

 was at once evident, from the total absence of ventral fins, that they entirely 

 confirmed the view I had previously taken of their being new in character, and 

 of the propriety of forming them into a genus distinct from that of the genus 

 Polypterus. 



Male and female different in appearance. — It was, however, also evident that 

 the fish could be divided into two apparently distinct varieties, suggesting at first 

 the idea that they might possibly be two species belonging to the same genus. 



One having the body nearly equal in depth in its whole length towards the anal 

 fin, with a distinct and well-developed anal fin and caudal extremity. While the 

 other had a more tapering form of body posteriorly, and a very small anal fin, 

 so small indeed, that when closed, and lying in its scaly groove, it might almost 

 escape notice altogether. 



On making a more careful examination, however, it was found that all the 

 fishes of the first variety were males, and those of the second were females. The 

 fact was therefore forced upon me, that this apparently strange and considerable 

 variety in form was entirely sexual in its character, although somewhat the 

 reverse of what we find in fishes generally, — the females being commonly distin- 

 guished from the males by the fuller and deeper form of their bodies,— and, as in 

 all other respects the characters of both fish seemed to agree, that the fish were 

 simply the male and female of the same species. 



I also exhibit a specimen of the female of this fish, of larger size than the 

 others, which was, with some other kinds of fish, politely sent to me from Africa, 

 a few months ago, by Mr W. G. Mylne. These fish are stated to have been 

 all collected by him in the district of the Great Camaroon mountains, on the coast 

 of which the missionary station of Victoria has within the last few years been 

 placed ; this new ganoid, therefore, also inhabits the] rivers of that still more 

 southerly and little-known region, and, accordingly, this gives us an additional 

 habitat for the fish. 



I shall now give a detailed description of the fish, both of the male and female, 

 and shall conclude with a summary of its characters, pointing out its general 

 relations to, and differences from, the allied genus Polypterus. 



* Mr Robb has recently sent me the following additional remarks on the native name of this 

 fish :• — "Many of the natives call this fish Nyung ; and this suggests another possible etymology. 

 Nyang is the stipule of the leaf of the mimho palm, which, being of a narrow ribbon shape, dries up 

 and remains twisted round the tree, from year to year, as long as the tree exists. The colour of 

 the dried stipule is like that of the fish ; and very possibly either the fish was named from Nyang 

 of the mimbo palm, or Nyang was named from the fish. In this latter case, which is not at all 

 improbable, the etymology is left undecided, and remains a matter of conjecture." 



