ASHFORD : ON BANDED LAND SHELLS. 89 



nov. spec, from New Guinea :" by Wm. Nelson ; " Descriptions 

 of Three New Species of Fhysa from Queensland : by William 

 Nelson and John W. Taylor — (the species described were P. 

 Brisbanica P. Beddomei and P. ftisifo?-f>ns) ; "Description of 

 Helix Petierdiana noY. spec, from Tasmania :" by John W. Taylor. 



SUGGESTIONS FOR A SERIAL ARRANGEMENT OF 

 THE VARIATIONS OF OUR BANDED LAND SHELLS. 



By CHARLES ASHFORD. 



(Read before the Conchological Society)- 



An examination of a large number of individuals of fi. 

 virgata, cape7-ata, ericetonnn and B. a cuius has led rue to observe 

 what appear to be analogous changes now going on in these four 

 species respectively, with regard to their colored ornamentation. 

 And, in selecting these four for consideration, I shall confine my 

 remarks within these limits, simply because I have had better op- 

 portunities for observing them, and not because I consider the 

 suggestions to be offered as inapplicable altogether to the other 

 banded species. 



I will not raise the question whether the three Helices above- 

 named derive their origin from a single remote ancestral species, 

 nor whether the descent of B. acutiis was at a still more remote 

 period a bifurcation from the same stemma, but the varied 

 ornamentation of their existing forms suggests the probability that 

 each species is derived from ancestors having the common charac- 

 teristics of (i) two well defined and continuous zones, one above 



