26 LAND AND FRESHWATER 



Section 2. Eight margin of the peristome straight. Con- 

 tains : — 



C . pliil i ppianmn (is a Cijdophorus). — ? 



C chtfhratulmn, Recluz. Yemen. 



C. v'Uellinum,Viv. Madagascar, Natal, iiec. Boche- 



hrunia, Bourguignat. 

 C. listeri, Gray. Mauritius. = JimhriaUim, Qnoy 



(==type of Liyatella, Martens). 

 C. Juemastoina, Anton. Isle of France. 

 C. politum. Sowerby. — ? 

 C. sjntrcum. Bombay. (Is a Cijclotopsh.) 

 C. piigmceum. New Ireland. 



Section 3. Right margin of peristome slightly expanded, 

 deeply sinuous. 



C. imdtilineaiam. Madagascar. 



Subgenus Lioatella, Martens ? =Rochel»-Hiiia, Bourg. Type 

 C. listen, Gray, Mobius, Meeresfauna Mauritius, &.c.., 1880. 



Monsieur J. R. Bourguignat, in ' Mollusques Terrestres et 

 Pluviatiles dans le Pays (^omalis Medjourtin,' IbSl, divides 

 Otojioma into three sections, founding two new subgenera. These, 

 on purely conchological grounds, may be accepted as being useful 

 for the identification of species, particularly of fossil forms, should 

 they be discovered. I therefore introduce them here: — 



1. Otopoma. 



Section 1. Umbilicus not covered, and with a slight angulation 

 on the columellar margin of the peristome. Type 0. bal- 

 fouri, G.-A. : Socotra. P. Z. S. 1881, p. 253, pi. xxvii. 



figs. 2, 2 ((. 



0. foliaceum, Chem., a Nicobar shell, and a Ci/clophori(s 



included by Bourguignat, must be removed, and there 



then remain with the above type : — 

 0. comjilanatam, G.-A. Socotra. P. Z. S. 1881, p. 254, 



pi. xxvii. figs. 3, 3 a. 

 0. clathraiuJum, Sowerby. Yemen. 

 0. socotranum, G.-A. . Socotra. P. Z. S. 1881, p. 254, 



pi. xxvii. fig. 4, as 0. clathratulum, var. socotrnna, G.-A. 

 0. clathratulum, var. minor, G.-A. Socotra. P. Z. S. 1881, 



p. 255, not figured. 



Section 2. Otopoma subgenus Georgia, Bourguignat, I. c. p. 65. 

 The umbilicus entirely covered with a thick callous reflexion 

 of the peristome. Type 0. naticoides, Ilecluz. Socotra. 



0. (Georr/ia) austeni, Bourguignat. Socotra. = naticoides^ 

 Rcciuz. P. Z. S. 1881, p. 252, pi. xxvii. figs. 1, 1 a. 



0. (Georgia) guUlaini, Petit, Jour. Conch, i. 1850, pi. iv. 

 fig. 3. Mogadoxa. 



0. (Georgia) clausum, Sowerby. Yemen. 



