On new MoIIusca from South Africa. 19 



Fi(j. 13. The same from below (also slightly modified from a figure given 

 by Thorell). 



Fi(/. 14. Gomihptes (an Opilio) to show the fusion of the anterior 4 (? 5) 

 abdominal tergites with the carapace and the 4 (l-4j free ter- 

 gites and 5 (l'-5') free sternites. 



Fig. 16. The same from below, for comparison with fig. 14. 



Fig. 16. Holothyrus (one of the Acari), for comparison with fig. 13, to 

 show the jointed, chelate mandible, and pediform palpi I., II, 

 (after Thorell). a, anus ; g, position of genital orifice. 



Fig. 17. Diagram of one of the Solifugje, to show the segmentation of the 

 carapace, the basal segment of the mandible (6) fused to the 

 cephalic shield, tlie position of the stigmata on the 2nd and 3rd 

 (morphologically, I think, the 3rd and 4th) segments of the 

 abdomen, and (s) the position of the cephalothoracic stigmata. 



N.B.^Where I have taken the liberty of utilizing figures published 

 by Dr. Thorell, I wish it to be understood that I have tested their accu- 

 racy by an examination of actual specimens. 



II. — Descriptions of Thirteen neio Species of Terrestrial MoI- 

 Iusca from South Africa. Bj James Cosmo Melvill, 

 M.A., F.L.S., and John Henry Ponsonby, F.Z.S. 



[Plate in.] 



This, our sixth contribution on the subject, we present in 

 fulfilment of our promise (Ann. & Mag. Nat. Hist. 1892, 

 vol. X. p. 237) to deal with new forms of Ennea and Pupa. 

 We now describe four of the former genus and seven of tlie 

 latter. 



1. Helix {Pella) strobilodeSj sp. n. (PI. III. fig. 1.) 



H. testa obtecte umbilicata, conica, tenui, sordide alba, epidermide 

 sericco-cornea contecta ; anfractibus sex, supra angustatis, infra 

 ad basin rapide accrescentibus, paullum ventricosis ; apertura 

 lunari ; peristomate teuui, simplici, apud umbilicum triaugulatim 

 reflexo. 



Long. 7-75, lat. 5-50 mill. 



Rah. Tharfield. 



A somewhat conical, close-whorled shell, with simple mouth 

 and narrow umbilicus, allied to H. Loveniy Krauss. 

 Two specimens. 



2. Helix [Patula] somersetensisj sp. n. (PI. III. fig. 2.) 



H. testa aperte umbilicata, subconico-depressa, laevi, albo-cinerea ; 



2* 



