6o PROCEEDINGS OF THE CONCHOLOGICAL SOCIETY, 



Helix cantiana var. albocincta. — This interesting 

 variation, which is characterised by a pale peripheral zone, or 

 band, usually most strongly marked near the aperture, 

 owing to the increasing intensity and darker colour of the 

 presumed confluent banding, occurs in several species and is 

 brought prominently forward so as to elicit, if possible, further 

 information upon those manifest traces of spiral banding (occa- 

 sionally occurring in shells usually unicolourous) which may be, 

 as some assert, nascent, but are more probably the rudimentary 

 expression of bands formerly existent. Latterly there has been 

 considerable discussion in 'Science Gossip' and elsewhere upon 

 this subject, originated by a statement made in a valedictory 

 address to this Society in 1887, but these discussions achieved no 

 useful end, as the point of dispute became quite removed from 

 the original statement, and a lengthy controversy arose upon 

 a subject about which — except perhaps for argumentative 

 reasons — there has been, we should imagine, no serious dispute, 

 viz. : the original colour of the nascent moUuscan shell in the 

 distant ages when the developing characters of the moUusca 

 were separating them from the allied groups, a point not at all 

 pertinent to the original statement which initiated the discussion. 



In our opinion it is very probable that these traces of 

 banding are not the early stages of banding in process of 

 development, but the vestiges of bands formerly existent and 

 derived from banded ancestors. This statement does not 

 affect in the slightest the question of the original colour of the 

 primitive moUuscan shell, but is intended to apply only to the 

 ancestral Helix or Helices from which we now assume our 

 obsoletely, as well as distinctly, banded Helices to have 

 descended. 



It is, we think, somewhat improbable that a number of 

 species of different habits and habitats should all simultaneously 

 evolve nascent bands of such an exactly uniform character and 

 arrangement. Should we not rather assign this remarkable uni- 

 formity of character and disposition of banded markings 10 



J.C. vii., April, 1892. 



