THE MOLLUSCS OP THE GREAT AFRICAN LAKES. 181 



The Molluscs of the Great African Lakes. — 

 II. The Anatomy of the Typhobias, with a 

 Description of the New Genus (Batanalia). 



By 

 J. E. S. Moore. 



With Plates 11—14. 



No entire specimen of Ty phobia has hitherto been described, 

 and we have consequently remained entirely in the dark as to 

 the real morphological character of what is probably the most 

 remarkable fresh-water Gastropod at present known. 



Presumably from the characters of its empty shell this genus 

 has been classed by the conchologists^ with the Melanias, as 

 a new sub-section of that group. ^ But into what serious error 

 determinations of this sort may lead, when based on conclio- 

 logical evidence alone, the present paper, which contains the 

 first anatomical description of the mollusc, will suffice to show. 



It will be seen that the structural features of the Typho- 

 bias, so far from establishing the above conchological antici- 

 pations, in every way confirm the conclusions at which I 

 arrived respecting the marine origin of these molluscs from a 

 study of the distribution of the African lake fauna in general.^ 

 Hence the actual facts of anatomy are, as I anticipated from 



» Smith, ' Proc. Zool. Soc.,' 1881, p. 276. 



* Fischer, 'Manuel de Conchyliologie,' p. 705. These determinations have 

 been particularly unfortunate, as they have masked the marine, and conse- 

 quently intensely interesting character of the molluscs of the lake. 



" The Molluscs of the Great African Lakes." I. " Distribution," 

 ' Quart. Journ. Micr. Sci.,' present number, p. 159. 



