CHAPTER VII 



THE SPIDER — A STUDY OF ANIMAL ARCHI- 

 TECTURE 



Most plants are rooted to the soil, while most animals are 

 free to move from place to place. Nevertheless many species 

 of animals, particularly the higher ones, have some place to 

 which thej^ repeatecUj^ return and which may be called their 

 home. This home is usually the place which serves to rear 

 the young and to shelter both them and their parents. 

 The simplest sort of a house consists of a lot of agglutinated 

 particles of sand enveloping the body of the animal. Within 

 this sand-tube the eggs may be laid. Such a tube of sand is 

 constructed bj^ many worms (page 188). Certain moUusks, 

 which are protected bj' hard shells, make burrows in rocks 

 in which they pass a part of their lives. When these moUusks 

 are very numerous (page 230) , the rocks ma}' be quite honey- 

 combed by their burrows. Manj' of the higher crustaceans 

 form more or less permanent burrows in the sea bottom, where 

 they may dwell and protect their eggs during the breeding 

 period. All of these sorts of homes, however, are very simple 

 architecturally compared with those of some insects, spiders, 

 and vertebrates. 



Certain burrowing insects, like the termites (page 26) and 



ants (page 53), build complicated communal homes -ndthin 



the earth. Others, like the wasps (page 51) and bees (page 



49), construct nurseries of mud, paper, or wax. In the group 



of spiders complicated structures have been developed, less for 



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