336 MANUAL OF THE MOLLTJSCA. 



CHAPTEE ly. 



ON COLLECTING SHELLS. 



The circumstances under -wliicli 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 hahitats, or geographical 

 localities of species, and the stations or circumstances in which 

 they are found : to the latter subject only slight 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 

 themselyes freely in the dews of morning and evening. Some 

 species, like Bulimus acutus, are found only near the sea; Bulimus 

 LacJihamensis 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 Clausilice maybe 

 obtained even in mild winter weather at the roots of trees ; the 

 small species oiPupa (or Vertigo) are sometimes taken abundantly 

 when sweeping wet grass with an insect net ; Acicula fuscaMyQS 

 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 aculecda 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 

 arhoreal in their habits. The West Indian palms (such as 

 Oreodoxa regia) are the chosen abode of many species of Heli- 

 cidge. M. Couthouy found Bulimus auris leporis on the orange 

 and myrtle-trees near Eio, and Partidce and Helicince, on the 

 Dracaenas 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 Achatince will sometimes lay 

 their eggs in captivity.* 



* Such giants reqxiii-e 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. 



