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atin canister, of sufficient size to hold all that may be se- 
cured at one time of species as large as Helix monodon, or 
larger. A large wide-mouthed bottle may answer the same 
purpose. The canister should have an easy fitting cover 
perforated for ventilation. The cork to the bottle may be 
perforated. For species less than HH. monodon (one-third 
inch diameter), a bottle of alcohol that may be carried in the 
vest pocket will be desirable. The larger species are picked 
up by hand without any aids. The small species are often 
80 fragile and so minute that a pair of delicate pliers, some 
_ like the light pliers used by watchmakers, but having wider 
"blades, will be ‘found so useful as to be indispensable. With | 
the pliers the small shells can be rapidly picked up and con- 
= Yeyed to the alcohol. The use of the alcohol is to contract 
_ the soft parts to the smallest dimensions, by extracting the 
water they contain. It leaves the shells in a cleaner condi- 
-tion than when they are allowed to crawl over and cover 
each other with mucus and dirt. If it be desired to preserve 
Specimens of those mollusks that are destitute of shells for 
= anatomical purposes, they should have a separate bottle of 
| alcohol to keep their mucus from enveloping the shells of 
Small species. 
To collect fresh-water shells the collector needs sometimes 
4 only his hands, especially in narrow rivulets where every- 
7 thing can be seen and reached from either side of the water. 
À He needs a bucket of water for larger species, —a bottle of 
alcohol for minute species that would be likely to become 
lost or broken by association with the larger. Usually only 
°? bucket of water is needed. For all those classes that crawl 
“n or burrow in mud, some sort of dredge bat 
| needed, The simplest device that can 4 
Suggested is a tin dipper (Fig. 1), the 
adle of which may be made of any con- mean 
Yenient length by adding thereto a light wooden rod. With 
* finely perforated instrument thus arranged, a film of mud 
With shells intermingled may be scraped up, the mud sifted 

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