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The common snail, Helix albolafa n type of the air- 



breathing mollusk8. Fig. SG repn iil of natu- 



ral Bize, in its shell. The opening to the lung is seen at a, 

 and at B is represented the heart and lung of the garden 

 slug ( Limax flavus). 



The eggs of the pond-snails are laid in transparent cap- 

 Bules attached t>> submerged leaves, etc. 

 Those of Phy* rostropha are laid in 



tin- early spring, ami three or four weeks 

 later from fifty to sixty embryos with 

 well-formed shells may he found in the 

 capsule. 



The eggs of Limnmus are laid late in 

 the spring in capsules containing one or 

 two egg>. and surrounded by a mass of 

 jelly. 



Land-snails and slugs lay their eggs 

 loose under damp leaves and stones, and Fio. 85.-siug; natural 

 development is direct, the young snail 

 hatching in the form of the adult. 



Various shells, such as Marginetta, Turbinella, etc., are 



Fig. 86.-^4, common snail, natural size; B, the heart and lung'. 



Btrung in bracelets and armlets by savages. Cypraa mo- 

 neta, the cowry (Fig. 87), is used for money, and other 



shells are worked into various shapes for wampum or 8 



