98 CURRENT LITERATURE. 



BuchneP, 0. — Hdix pomatia, L. Revision ihrer Spielarten und Abnormitatem 

 mit Hervorhebung wurttembergischer Vorkommnisse nebst Bemerkungen liber 

 falsche Anwendung des Begriffes " Varietat." Jahr. d. Vereins f. vaterL Nat. 

 in \Vlirth., 1899, pp. 232 — 79, T. i — iv. 



This paper is divided into two parts. The first part consists of a discussion as to 

 the use of the term " variety," and does not seem to reach a more satisfactory con- 

 clusion than previous discussions of the same point. Usage has given to the term 

 " variety" a very wide and a very loose signification ; and any accurate definition 

 or classification is practically impossible till more is known about the causes and 

 conditions of production of the various deviations from the " typical" form. The 

 ideal classification of varieties must depend on a knowledge of their physiological 

 causation. The author adopts the satisfactory plan of calling the deviations usually 

 classed as " varieties " by the less committal term of " forms." 



The second part of the paper consists of an examination of the described varieties 

 oi H. pomatia: the following is a summary of the author's results: (i) forma 

 nortnalis s. vulgaris ; last whorl more than two-thirds of and nearly three-quarters 

 of the total altitude ; diani. 40 to 50 mm. : (2) forma inflata, Hartmann ; much 

 bigger and often thinner-shelled than the type, whorls more swollen and more de- 

 pressed, so that the last whorl is four-fifths to five-sixths of the total height : (3) 

 forma sphaeralis, Hartmann ; larger and as a rule thicker-shelled than the type, 

 more conical, apex rounded, last whorl about two-thirds of total altitude : (4) forma 

 plagiostoma, Ikichner ; nearly always smaller than the type, fairly high-spired, 

 generally light brown with narrow bands, owing to a downward deviation of the 

 last whorl the mouth is more obliquely elliptical than in the type: (5) forma hirrita, 

 auctt. : very variable in size, thick-shelled, cone-shaped with a produced spire, last 

 whorl one-half or even one-third of total altitude: (6) loxxa.-^ grandis, auctt. ; diam. 

 60 to 68 mm.: (7) forma /arz/a, Buchner; diam. 30 to 34. The last two forms 

 coexist with one of the others ; besides which we may have specimens of a sphaeralis- 

 lurrita character: (8) aberratio sinistrorsa Rossm. : (9) degeneratio a//^«r«;j-; the 

 author admits the existence of genuinely albino specimens ; they are as a rule 

 thinner-shelled than normal and the periostracum is usually decayed to some extent, 

 these characters being expressi<jns of the generally pathological state of the animal 

 which is most obviously exhibited in the absence of pigment. If such is really the 

 case, the condition is scarcely aptly described as a " degeneration:" (10) deformatio 

 scalaris, Miiller. The illustrations (29 in number) are very good. — ARTHUR E. 

 Boycott. 



Crick, G. C. — On some new or little-known Goniatites from the Carboniferous 

 Limestone of Ireland. Ann. and Mag. N. IL, 1899 (s. 7), vol. iii, pp. 

 429—54, figs. I — 15. 



The author here redescribes de Koninck's type specimens of Goniatites [ = reri- 

 cyclus] plicatilis and G. [Brancoceras] ortuitissimus, which he was fortunate enough 

 to identify during a visit to the Museum of the Geological Survey of Ireland. In . 

 addition he describes the following new species : Pericydus foordi, P. trapezoidalis, 

 P. rotuliformis, P. danensis, P. bailyi, P. subpiicatilis, Glyphioceras cordatuvi, 

 G. corpulentum, G. dlipsoidale, and Prolccanites leesoni. — W. E. C. 



Crick, G. C. — Note on Ammonites enomphalus, Sharpe. Geol. Mag., 1S99, 

 vol. vi, pp. 251 — 56, figs. I — 2. 



Mr. Crick has recently examined a specimen of this interesting fossil from the 

 hard Cenomanian Limestone close to \VhitIands, west of L}'me Regis, which is 

 carefully described and compared with the specimens described by Sharpe (1854) 

 and Jukes- Browne (1896). Its affinities are briefly described, and for the present it 

 is placed in the genus Douvilleiceras. — W. E. C. 



PilsbPy. H. A. and Coekerell, T. D. A. — Ashmundla, a new genus of 

 Helices. Proc. Acad. Nat. Sci. Phil., 1899, pp. 18S— 94, figs. 1—3 



