122 



TJie Study of A nimal Life 



FART I 



details. Those of the land-crabs {Gecarcinus), the wood- 

 cutting bees {Xyhcopa), the sand-martens, the marmots, the 

 rabbit, the prairie dogs, illustrate this kind of dwelling in 

 various degrees of perfection. 



The male stickleback {Gasterosteus) weaves and glues 



Fig. 27. — Swallows {Chelidoiiaria urbica) and their nest, (.\fter Erehm.) 



the leaves and stems of water-plants ; the minutest mouse 

 {Mus miimtiis) twines the leaves of rushes together ; the 

 squirrel makes a rougher nest ; the orang-utan and the 

 chimpanzee construct shelters among the branches ; but the 

 nests of many birds are by far the most perfect works of 

 animal art. 



Of buildings, the swallows' nests by the window, and the 



