JOURNAL OF CONCHOLOGY. 1 23 



(Tyrian purple) — is in reality h^emolymph extruded as the 

 result of some forcible rupture of the tissues on the part of the 

 animal, which on exposure to the air becomes oxidised and 

 consequently of a bluish color due to the h^mocyanin it contains. 

 Of course, it would be exceedingly difficult to demonstrate any 

 such rupture in the tissues, but it certainly bears the face of 

 probability. It is interesting to note also that this hsemocyanin 

 exists also in the h^molymph of Helix pomatia, H. aspersa 

 and Paludina vivipara and that it seems to function as the 

 haemoglobin in the plasma of the haemolymph of Planorbis. 

 Mac Munn("Chromatology of Blood of some Invertebrates," 

 Quart. Journ. of Micros. Science, 1885) finds no absorption 

 bands in the hsemocyanin of the haemolymph of these species. — 

 J. W. Williams. 



ON THE VARIETIES OF OUR BANDED SNAILS, 

 ESPECIALLY THOSE OF HELIX CAPERATA Mont. 



By rev. S. spencer PEARCE, B.A. 



(Read before the Conchological Society, June 5th). 



Among the many questions that await solution at our hands, 

 none would be more full of interest than that which would help 

 us to elucidate the purpose and meaning of the infinite variety 

 of markings and colouring, or the manifold differences in size 

 and shape occurring in the shells of such molluscs as Helix 

 virgata, Helix caperata, Helix ericetorum; dind. BuUjjius acittus. 

 The endless diversity shewn in the varieties of these shells 

 is obvious to the most casual observer. There is no doubt 

 that, if we could interpret aright these variations in shape, size, 

 or markmgs, they would make clear to us very much which is 

 now dark and inexplicable in the life histories of these species 

 For the conchologist, like all other enquirers into nature, 



