ON COLLECTING SHELLS. 187 
The following are examples of the elevations at which land- 
snails haye been found. (pp. 289, 294.) 
Helix pomatia, 5,000 feet—Alps. (Jeffreys.) 
» rupestris, 1,200—5,000 ft. 
»» bursatella, Gould, 2,000—5,000 ft. Taheiti. 
Bulimus vibex, 7,000 ft. India. (Benson.) 
5 nivicola and ornatus, 14,000 ft. a 
is Lamarckianus, 8,000 ft. New Granada. 
Achatina latebricola, 4—7,000 ft. Landour. 
Pupa Halleriana, 1,200—2,500 ft. Alps. 
», tantilla, 2,000 ft. Taheiti. 
Clausilia Idea, 5,500 ft. Mt. Ida. 5 
Vitrina glacialis, Forbes, 8,000 ft. Monte Rosa. 
», annularis, 2,000—3,000 ft. Burgos. (M‘Andrew.) 
» Teneriffe, 2,000—6,210 ft. Madeira. 
Helicina occidentalis, Guilding, 2,000 ft. St. Vincent’s. 
(Limnza Hookeri, 18,000 ft. Thibet.) 
The land-snails of warm and dry regions remain dormant for 
long periods (p. 14), and require no attention for many months 
after being collected.* 
Freshwater shells are collected with an insect net or “‘ landing 
net’ of strength suited to the work of raising masses of weed. 
The strongly rooted flags and rushes may be pulled up with a 
boat-hook; and Cyclades, as well as uniyalves, may be obtained 
by shaking aquatic plants over the net. For getting up the 
pearl mussels, the most efficient instrument is a tin bowl, per- 
forated like a sieve, and fitted on the end of a staff, or jointed 
rod. (Pickering.) 
In some situations the fresh-water shells are all much eroded 
(p. 33,), or coated with a ferruginous deposit. It may be 
desirable to find out the localities where the specimens are 
in best condition before collecting extensively. The opercula 
should always be preserved with the shells to which they 
belong; those of the Cyclostomide and Melaniade are particu- 
larly interesting. 
The Auriculide are especially met with in damp places by the 
sea; Im mangrove-swamps, and creeks and river-banks where 
the water becomes brackish. Amphibola and Assiminea are 
found in salt-marshes, Siphonaria and Peronia on the shore, 
between tide-marks. 
Collecting Sea- shells.—The following remarks are from the pen 
* Land and fresh-water snails may be killed instantaneously with boiling water, if a 
few are done at a time; and cooled by removal to cold water. Every collector finds 
expedients for removing the animals more or less completely from their shells ; those 
which, like Clausilia, retire beyond the reach of a bent pin may be drowned in tepid 
water, 
