INTRODUCTION. 5 
tion is suspected to be comparatively recent, are S. ovale, 
D. polymorpha, H. Pisana, and H. obvoluta. 
It was thought that H. pomatia was introduced by the 
Romans as an article of food, but this notion is now dis- 
carded. 
Ways and Means of Collecting. 
I have often been asked by would-be collectors such 
questions as “How do you set about collecting?” 
“What implements are necessary ?”’ and most frequently, 
perhaps, “ Where do you look for shells? I know the 
‘garden snail,’ and a yellow one with bands, but I never 
see all these you have in your cabinet.” 
To those desirous of this and similar information the 
following hints may prove serviceable :— 
When going out for a ramble after shells very few pre- 
parations are necessary. For pond work a scoop is essen- 
tial, and better than a net. The most handy scoop is one 
of very fine zinc gauze, with a sharp zinc rim, to which is 
attached an open ferrule, into which a walking-stick may 
be inserted. A store of tin boxes of various sizes is re- 
quired, and in selecting these it should be remembered that 
those which open with a spring are more handy than those 
the lids of which have to be removed every time a shell is 
dropped in. Small nib-boxes and match-boxes are very 
good for small shells, and should be padded with a little 
weed or moss to prevent the more delicate species being 
broken by being rattled together in the pocket. Tin boxes 
