660 MANUAL OF NATURAL HISTORY. 



mical purposes. The Malays and Chinese collect 

 great heaps of shells for the purpose of burning 

 them into lime for mixing with their betel-nut and 

 sirih-leaf for chewing. Fluviatile shells must be 

 obtained by the spoon and the water-net, except in 

 lakes, where the dredge may be employed. Many 

 species are found adhering to the under surface of 

 dead-floating leaves, or clinging to old trees and 

 logs in the water, or crawling on the stones partially 

 out of the water, or along the oozy banks ; while 

 many again will be discovered partially or entirely 

 buried in the mud. Land shells are taken in the 

 greatest abundance after showers and early in the 

 morning, or during the evening and night ; they 

 are found crawling on the leaves of plants or on the 

 the ground among damp moss and dead vegetable 

 matter, under heaps of stones or loose bark of 

 trees, or in holes of their trunks and fissures of the 

 bark, or along pathways, and in fields, woods, and 

 heaths. Many of the smaller kinds may be taken 

 by sweeping the bushes with a net. 



The littoral species of Mollusca are found on the 

 reefs and rocks which the sea leaves uncovered on 

 the receding of the water, and where they hide under 

 the stones until the tide returns. They are often 

 most numerous after a storm ; stones must be turn- 

 ed, the heaps of sea-weed raised and their roots 

 examined, the little pools must be explored, fis- 

 sures of rocks peeped into, and coral-masses broken 

 and uprooted. Starfishes, and other Echinoderms 

 and Sponges must be very carefully examined for 



