32 CURRENT LITERATURE. 



the genus Uivcvcliis, which appears not to occur in Cape Colony proper. 

 Krauss gave a very poor description, but he stated the mantle had no slidl, and 

 that the creature was abundant in gardens in Cape Colony. Possibly it was an 

 Oopclta ; its colour was said to be greyish-black. — T. D. A. Cockerell. 



CoUinge, Walter E.— On the Anatomy of a Collection of Slugs from N.W. 

 Borneo ; with a List of the Species recorded from that Region. Trans. 

 Roy. Soc, Edinr., 1901, vol. xl., pp. 295 — 312, pis. i — iii. 



The present communication, the author points out, is to be regarded more 

 in the light of a preliminary notice of species, which, as further material is 

 obtained will receive more exhaustive treatment. 



After a short introduction on the Bornean Slug-fauna, the author re- 

 describes the genus Daiiiayaiitia, Issel, and gives coloured figures of D. dilccfa, 

 Issel ; a new species, D. carinata, is described and figured, as also the genera- 

 tive organs and dart. Wicginannia is a new genus containing IF. diibiiis, 

 Wgm., W. gigas, IV. poiisoiibyi, and IF. bonieciisis, nn. spp. The generative 

 organs of Colli iigea siiiitlii, Cllge. and Godw.-Aust., are ne.xt described and 

 figured. A further new genus, IssLieniia, containing two new species, plica ta 

 and globosa, is next dealt with, and Veronicella sluifordiaiin, V. exiina, and 

 Onchidimn poiisoiibyi, nn. spp. are figured and described. 



A list of the species of slugs recorded from Borneo, twenty-seven in 

 number, with the original references concludes the paper. 



Williamson, M. Burton.— How Potamidcs (CcrctUidca) calitoiiiica, Hald., 

 travels. Naut., 1901, vol. xv., pp. 82, 83. 



Mrs. Williamson has noticed that in travelling over the mud-flats, this 

 mollusc leaves a zig-zag pattern, which is made by the apical whorls of the 

 shell as it is dragged forward, or sideways. From a series of observations 

 upon its mode of crawling, the authoress concludes that the foot movement is 

 somewhat secondary. The animal pushes its head forwaid, expands its tenta- 

 cles to their full extent, then with an effort raises the body whorl, and the shell 

 is propelled forward before the foot advances. Immediately following these 

 nioven.ents, the foot is spread out and drawn forward. 



Kennard, A. S. and Woodward, B. B.— The Post-Pliocene non-marine 

 Mollusca of the South of England. Proc. Geol. Assoc, 1901, vol. xvii., 

 pp. 213—260, figs. 32—37. 



This valuable and important paper is, apart from its geological interest, full 

 of interest to the student of recent shells. While endeavouring to avoid altera- 

 tions in the nomenclature, a few wise changes have been made, thus we read 

 Poniatias rcflcxiis (L.), in lieu of Cyclostonia dcgaiis, Miill., Paliidcsiriiia stagiialis 

 (Bast ), in place of Hydrobia idvae, Penn. ; SpJiyradiiitii cdciitiiliiiii (Drap), is 

 removed from Vertigo, while Hcliaila barbara (L.) replaces Biiliiuiis aciitiis, 

 Miill. 



In all the authors' list 138 species of non-marine Mollusca as existing in 

 this country, and 10 extinct forms, of these 129 occur in the Soutii of England, 

 and 7 of the extinct forms. 



In this and preceding papers the authors have accumulated a large mass 

 of evidence, which now enables them to speculate on the origin and duration 

 in this country of the various constituents of our molluscan fauna. It must, 

 however, be borne in mind that these speculations are only tentative. The 



