HELIX-LEUCOCHROA. 55 



SUPPLEMENT TO HELIX. 



The following pages contain descriptions of species which have 

 been made known since the publication of the various parts of this 

 work treating of the genus Helix, and also of certain species 

 omitted in the body of the work. 



Genus SAGDA (Vol. Ill, p. 5). 



From this group must be removed the species oireumfirmata Redf. 

 and discrepans Pfr. (p. 9), of Bermuda. These belong to PCECILO 

 ZONITES, a genus of Zomtidce (Vid. Proc. Acad. Nat. Sci. of Phila. 

 1888, p. 285). 



Genus LEUCOCHROA (Vol. Ill, p. 10). 



KOBELT, in his continuation of Rossmiissler's Iconographie (new 

 series, vol. iii, p. 29-43, 1887), has discussed this group with his 

 accustomed acumen, and has illustrated a large series of specific 

 and varietal forms. He seems to consider H. thayaca and H. 

 titan odolena of Bourg. as mere varieties of H. otthiana, butspiRONO- 

 MALA (pi. 21, figs. 10, 11) he thinks is a well-defined and distinct 

 species. 



L. CANDIDISSIMA var. SARDOA Maltzan. 



Illustrations of this Sardinian species or variety are given by 

 Kobelt ; the form has been referred to bcetica by some, to rimosa 

 Christ, and Jan by other authors. It is probably a local variety or 

 sub-species of candidissima. 



L. OCTINELLA Bourguignat. PI. 21, figs. 7, 8, 9. 



See Manual iii, p. 13. The figures here given are from Kobelt. 

 This form differs from cariosula in the much stronger keel, and the 

 rougher sculpture, but intermediate specimens will probably be 



found. 



St. Denis au Sig S.E. of Oran. 



L. DEBEAUXI Kobelt. PI. 21, figs. 4, 5, 6. 



The sculpture consists above of close, irregular wrinkles, which 

 are coarser and more uneven than in octinella and Kobeltiana ; the 

 whorls are shouldered, the last whorl becoming rounded toward the 

 aperture, by the obsolescence of the keel. This seems to be a species 

 distinct from Kobelti and mayrani. 



Near Nemours, and Leila Marnia, Algier. 



