45 



ON THE OCCUEEENCE OF PUPISOMA IN SOUTH AFEICA. 

 By Hknry C. Burnop. 

 Read 12th January, 1912. 

 Through the generosity of Mr. J. H. Ponsonby in placing at my 

 disposal for study and comparison every specimen of Pupisoma in iiis 

 collection, I have been enabled to identify two representatives of 

 the genus in South Africa; and through the kindness of Mr. H. 

 Suter and Dr. H. A. Pilsbrj- in checking and contirming ray tentative 

 conclusions, 1 am able to publish the results of my investigation. 



1. PCTPISOMA ORCULA. (BeUS.).^ 



Originally described from India, this species is widely distributed 

 through South Africa, specimens having been examined by me from 

 Port Elizabeth (Crawford, per Ponsonby), Grahamstown (Farquliar), 

 Pretoria (Connolly), Victoria Falls, Zambesi (Warren and Connolly), 

 and the following localities in Natal: Richmond (Wakefield and 

 Cooper), Karkloof (Taynton and Burnup), Maritzburg, Edendale, 

 Dargle, and Ntimbankulu, Mid-Illovo (Burnup). 



Under a strong lens fine, undulating, spiral striae may be seen in 

 the spaces between the oblique costulate growth-lines, especiallv on 

 the base, a feature not recorded in Benson's original description. 

 Tliis is not confined to the South African specimens, but has also 

 been observed in the examples from India, Java, and Japan that 

 I have examined. 



In Natal the shells are found on the trunks, branches, and leaves 

 of Cusso7iia and other native shrubs and trees in woods, as well as 

 on orange- and apple-trees in orchards. Mr. Wakefield, of Richmond, 

 attributes to these snails a beneficial influence in the matter of 

 clearing orange-trees of scale, but I have not been able to obtain 

 further confirmative evidence on the subject. Sometimes a distinct 

 varix, showing a former resting-place, is formed upon the shell. 



It is difficult to decide in these minute, thin-lipped shells when 

 maturity has been reached ; therefore to record average dimensions 

 of the shells measured would be misleading. I have, however, chosen 

 a few shells which seem mature, and hereunder give their dimensions — 



^ Helix orcula, Bens., Ann. Mag. Nat. Hist., ser. ii, vol. vi, p. 251, 1850. 

 Eeeve, Conch. Icon., vol. vii. Helix, pi. 174, fig. 1176, 1853. Pzqm 

 {Pupisoma) orcula, G. Nevill, Handlist Moll. Ind. Mus., i, p. 192, 1878. 

 Pupisoma orcula, Pilsbry, Man. Conch., ser. ll, vol. ix, p. 52, 1894; 

 Hirase, Conch. Mag., vol. iii, pi. ix, figs. 30, 31, 1909. 



