CURRENT LITERATURE. 43 



Stages with the account given by Ileymons {Zeitschr. f. wiss. Zool. 1S93) of the 

 development of the allied mollusc Umbrella mediterranea, and also with Conklin's 

 account of Crcpidula, from which it appears that on the whole Tcthys has a much 

 more regular segmentation. 



There have have been difficulties in the research. The animals are apparently 

 not easy to obtain, and the spawn is difficult to keep alive and normal. This last 

 spring (1898) none was obtainable. 



For the rest — the segmentation is unequal, and of the spiral type known in 

 various molluscs ; but for the exact "cell-lineage" of the micromeres and macro- 

 meres we must refer to the full description and the figures. The three plates in 

 execution and clearness of shading certainly leave much to be desired, but we 

 gather from a " Note" at the end of the paper that this has not been altogether 

 the author's fault. 



Of the later embryonic and larval stages the account is brief. Dr. Viguier has 

 evidently, on account of the difficulty of rearing, not had quite enough material in 

 these older periods at his disposal. We concur entirely in his remarks as to the 

 great interest and importance attaching to careful studies of the later transformation 

 of the larval Opisthobranchs. — W. A. Herdman. 



Sturany, R. — Catalog der bisher bekannt gewordenen Slidafrikanischen Land-und 

 Siisswasser-MoUusken. Denk. K. Akad. Wiss. Wien, 1898, Bd. Ixvii, pp. 

 537-642, 3 pis. [Jan. 1899.] 



Melvill, J. Cosmo, and Ponsonby, J. H.— A Contribution towards a Check- 

 list of the Non-marine Molluscan Fauna of South Africa. Proc. Malac. Soc. 

 Lond., 1898 (Deer.), vol. iii, pp. 166-184. 



The faunal regions dealt with in these two papers vary somewhat, for while 

 Dr. Sturany includes the country up to the Zambesi, Messrs. Melvill and Ponsonby 

 draw the line at the Tropic of Capricorn. Unfortunately the former author appears 

 — though he gives a lithographed supplement dated November — to have been 

 unaware of the latter authors' paper (Ann. Mag. N.H., August 1898, (7) vol. ii, 

 pp. 125-30, pi. vii), as also Sowerby's " Appendix to the Marine Mollusca,." 



The most striking feature is the great abundance of the genus Eyinea. No less 

 than 73 are quoted by Dr. Sturany and 75 by Messrs. Melvill and Ponsonby. One 

 species [E. obovata) quoted by these latter authors appears to be omitted from 

 Dr. Sturany's list : it would also be of interest to know his authority for quoting 

 E. zangucbarica as S. African. Morelet, when describing it, appears not to have 

 properly stated its locality, but the very name is a note of warning. Dr. Sturany 

 criticises, and with some show (if reason, the figures given by the English authors, 

 but when he complains (p. 542) that the basal tooth in E. perspicua is not shown in 

 the original drawings, he seems a little hypercritical, as it is described as "interna." 



The classification of the Helicoid and Zonitoid land shells appears to vary 

 greatly in the two lists : perhaps it will be long before this is properly cleared up, 

 as the anatomy is unknown in most cases. While Dr. Sturany gives 118 species, 

 Messrs. Melvill and Ponsonby give 105 for their more restricted region. 



It may be pointed out that Pclla, used by Dr. Sturany, is preoccupied in 

 Coleoptera : many other points of difference as to the value of certain names 

 arise, too elaborate in their nature to be dealt with here, but it may be remarked 

 that Helix fanuUis (Sturany, p. 588) is the young of a species of Ennea. 



The slugs do not appear to be very numerous, less than a dozen species in all ; 

 while Dr. Sturany quotes Agriolimax Icevis, the English authors quote A. agrestis, 

 and appear to have overlooked Urocyclus hirkii and Oncidium peronii. 



The Achatinidce are, as would be expected, fairly numerous ; we note that in 

 the English authors paper A. schcncki does not appear. Buliminus is well repre- 

 sented as are the Pupidx. Buliminus vitellinus appears to have escaped the notice 



