10 CyECILIOIDES OF CENTRAL EUROPE. 



etc., p. 128, pi. 13, f. 43 (teeth and genitalia). MELVILL and 

 PONSONBY, Proc. Malac. Soc. Land, iii, 184 (in S. Africa). 

 BINNEY, Manual of American Land Shells, p. 429. SORDELLI, 

 Atti Soc. Ital. de. Sci. nat. xiii, Milan, 1870, p. 48, pi. 1, f. 

 22-26 (otocysts, jaw, radula). Bucdnum terrestre MONTAGU, 

 Test, Brit. p. 248, pi. 8. f. 3. Helix octona GMELIN, Syst. Nat. 

 13, p. 3653. Achatina alba BROWN, Illustr. Land and Fresh- 

 water Conchology of G. B. and I., 1845, p. 32 (erroneously 

 quoted as of Turton). Achatina, pmilla SCACCHI, Catal. Conch. 

 Reg. Neapolitan!, 1836, p. 16. Columna miliaris de CHRISTOFORI 

 et JAN, "Shell fusiform-ovate, imperforate, smooth, glossy, 

 slender, whitish, the last whorl ventricose (1^ lines long, \ 

 wide), aperture oval, 1 line long, ^ wide)." Catalogus etc., 

 Mantissa, p. 2, 1832. Acicula kyalina Bielz, PAULTJCCI, Bull. 

 Soc. Malac. Ital. xii, 1886, p. 45 (Italy). Stenogyra octona var. 

 danica SCHLESCH Ann. Soc. Roy. Zool. et Malac. Belgique xli, 

 1906, p. 184. 



Gwyn Jeffreys' description of this common species is given. 

 It seems to be a rather variable form, but the limits of variation 

 in this group are little understood. A large proportion of the 

 specimens in collections are from drift debris of rivers, hence 

 forms from various colonies and diverse stations are mingled in 

 unwonted company. Such lots are misleading in the study of 

 variation. 



Var. elongata Locard. Of a slimmer, more lengthened form. 



Var. ventricosa Locard. Of the same size (not over 4.5 mm. 

 long), but the shape is a little more ventricose, more swollen at 

 the base (Locard, Conchyliologie Portugaise, in Archives du 

 Mus. d'Hist. Nat. de Lyon, vii, 1899, p. 141). 



Var. festuca Porro. Whorls only 4; size smaller, alt. 2, diam. 

 0.5 mm. Como and Varese, Italy. (Achatina acicula var. fes- 

 tuca Porro, Malacologia terr. e fluv. della Prov. Comasca, Milan, 

 1838, p. 52.) 



Var. eburnea (Risso). PI. 1, fig. 9. Shell very long fusi- 

 form, very fragile, glossj', pellucid, ivory-white; spire long, the 

 apex obtuse; whorls 7, regularly increasing, flattened or slightly 

 convex, separated by a deeply impressed suture, the last one- 

 third the total length. Aperture piriform, dilated below; colu- 



