136 MANUAL OF THE MOLLUSCA. 
CHAPTER IV. 
ON COLLECTING SHELLS. 
The circumstances under which shells are found is a subject 
so intimately connected with the methods of collecting them, as 
to make it undesirable to treat of them separately. 
Naturalists distinguish between the habitats, or geographical 
localities of species, and the stations or circumstances in which 
they are found: to the latter subject only sight allusion has 
been hitherto made (p. 7). 
Land-shells are most abundant on calcareous soils (p. 29), and 
in warm and moist climates. The British species are collected 
with advantage in autumn, when full-grown, and showing 
themselves freely in the dews of morning and evening. Some 
species, like Bulimus acutus, are found only near the sea; Bulimus 
Lackhamensis ascends beech trees on the Chalk downs and Cots- 
wolds; Pupa Juniperi and Helix umbilicata occur chiefly on 
rocks and stone walls. The moss-frequenting Clausilie may be 
obtained even in mild winter weather at the roots of trees; the 
small species of Pupa (or Vertigo) are sometimes taken abundantly 
when sweeping wet grass with an insect net ; Acicula fusca lives 
at the roots of grass; Cionella acicula is found in old bones 
(such as occur in Danish burial-grounds!), and occasionally in 
moving garden-bulbs; Helix aculeata has been met with on the 
under sides of leaves (e.g. the sycamore), a few feet from the 
earth. 
In tropical countries a large number of the land snails are 
arboreal in their habits. The West Indian palms (such as 
Oreodoxa regia) are the chosen abode of many species of Heli- 
cide. M. Couthouy found Bulimus auris leporis on the orange 
and myrtle-trees near Rio, and Partule and Helicine, on the 
Draceenas and Bananas of the Polynesian Islands; and the 
sailors of H.M.S. Rattlesnake, in Captain Owen Stanley’s 
expedition, became expert in collecting Geotrochi in the trees of 
the Australian islands. 
The great tropical Bulimi and Achatine will sometimes lay 
their eggs in captivity. 
* Such giants require to be collected in a basket, while the small land-shells of 
open and rocky countries may be put in a cotton bag, hung on a coat button. 
