338 SMITH : NOMENCLATURE OF CERTAIN GENERA. 



Schumacher in 181 7 first of all introduced this term 

 {Hyali7^a^) and the shell he described forms a section of 

 Marginella which may be retained. 



In 1819 Ferussac gave the name Hyalince to a section of 

 Aplosfomce, a group of ffelicella, which he called a subgenus of 

 Helix. The first species quoted by him under this head is 

 H. olivetornni of Gmelin. He also included H. glabra, H. 

 cellaria, &c. He did not intend Hyalina; as a subgeneric term, 

 but merely to be descriptive of certain species which he 

 enumerates. In the same way he used the iexxn ^ Fascia he' 

 for another group of species. 



Studer in 1820 created a genus Hyalina, but this is 

 synonymous with Viirina of Draparnaud, 1805. 



In 1837 Charpentier established the genus Hyalinia, as 

 understood at the present day, including therein H. glabra of 

 Studer, H, ///Vcwi- Mich, and Ferus., and H. nitidula Drap. 



Hyalina or Hyalinia is so generally accepted by Continental 

 writers that I feel disinclined to suggest the use of any other 

 name for our British species. However, to be consistent I 

 must do so, and therefore propose that Vitrea of Fitzinger 

 should be employed. This genus was published four years 

 before Hyalinia and agrees precisely with that genus in its scope. 

 'I'he only species mentioned by Fitzinger under his genus 

 Vitrea is V. crystallina, and this therefore must be regarded as 

 the type. Some Continental authors consider this and allied 

 species sufficiently distinct from cellaria Muller, and its allies, 

 to form a generic or subgeneric group, and therefore apply the 

 term Polita of Held to the latter species. For H. nitidus 

 Muller, Lehmann has proposed the subgenus Zonitoides, and H 

 fiilvus falls in Fitzinger's genus Co nidus. Conchologists who 

 have an inclination for minute sectional divisions may therefore 

 range our British species thus : — 



I Whether this section hold good or not, the name having once been used cannot again 

 be employed for any other group. 



J.C., vi., Apr,, 1 891. 



