SMITH : MOLLTJSCA OF LAKE TANGANYIKA. 93 



EuMELLA. 



Rumella, Bourguignat : i, p. 89 ; ii, p. 40, pi. xvii, figs. 20-37 ; iii) 

 p. 250; Martens, p. 214, pi. yi, tig. 47. 

 I do not at present see any sufficient reasons for specifically 

 separating any of the forms described by M. Bourguignat. R. neriti- 

 noides (Smith), therefore, will stand as the sole representative of this 

 genus. The other names are R. caUifera, Giraudi, glohosa, Jouhertij 

 Lavigeriana, Milne-edwardsiana. (Bourguignat, ii, iii.) 



KUMELLA NEEITINOIDES (Smith). 



Lithoglyphus neritinotdes, Smith: iii, p. 426; ii, p. 287, pi. xxxiii, 



fig. 19. 

 Litlioglyphus neritoides (sic), Pelseneer : p. 106. 

 Tang any iciai^^ neritinoides, Crosse: p. 126. 

 Stanleya neritoides (sic), Bourguignat : i, p. 87. 

 Stanleya neritinoides, Maxtens: p. 214. 



Stanleya. 



Stanleya, Bourguignat: i, p. 86; ii, p. 40, pi. xvii, figs. 13-15; iii, 



p. 246; Martens, p. 214. 

 Coulhoisia, Bourguignat: ii, p. 40, pi. xvii, figs. 16-19; iii, p. 247; 



Martens, p. 214. 



Stanleya eottjndata, n.sp. 



Stanleya neritoides, Bourguignat (nee neritinoides, Smith) : ii, p. 39, 

 pi. xvii, figs. 13-15; iii, p. 246. 



A series of curious mistakes has occurred in connection with this 

 species and the genus Stanleya. When founding that genus M. Bour- 

 guignat ^ gave as his type the Lithoglyphus neritinoides of Smith, 

 associating with it at the same time two other species for which he 

 subsequently founded his genus Coulhoisia. But the shell which 

 he regarded as the Lithoglyphus neritinoides was perfectly distinct 

 from that species, which, however, practically constitutes the genus 

 Rumella. Under these circumstances it becomes necessary to rename 

 the shell mistaken by Bourguignat for neritinoides, and to apply the 

 generic name Rumella to the true neritinoides. Later M. Bourguignat 

 thought it necessary to separate his Stanleya Giraudi and S. Smithiana 

 from his S. neritoides (sic), and to found for them the genus Coulhoisia. 

 This, however, in my opinion, was unnecessary, for, with the exception 

 of some slight difference in form, they are all practically of the same 

 general character. 



The genus Stanleya appears to be closely related to Rumella, but 

 has the spiral lines engraven in the shell, whereas in Rumella they are 

 superficial. Also the columella callosity is less strongly developed. 

 I have never seen any examples of this genus. 



' " Mull, region merid. Tangauika," 1885, p. 8G. 



