SOME STRANGE NESTS 185 



birds themselves are different in their habits 

 from ordinary swifts in often perching, like 

 swallows, on trees ; other swifts, as can be 

 noticed with our kind, never perch, but only 

 cling to things or creep into holes. Tree-swifts 

 build their nests on the branch of a tree, and 

 the nest is about the smallest any bird does 

 build, in proportion to the size of the builder ; 

 it is only about the size of the bowl of a tea- 

 spoon, and is stuck to the bough in such a 

 way that the bird sits on the branch and can 

 cover the egg with its breast at the same 

 time. There is only room for the single egg, 

 and the nest is quite too small to be sat in. 

 It is made of saliva like that of the edible-nest 

 swift. 



The last strange style of nest I shall mention 

 here is not so much a nest as a prison-cell ; 

 there is no " building " about it, as it is simply 

 a hole in a tree with the entrance walled up, 

 and the hen bird is shut up inside it. This 

 strange performance is the queerest habit of 

 the hornbills, those strange top-heavy looking 

 birds with short legs which seem out of all 

 proportion to their huge beaks and heads. 

 They always have them at the Zoo, and 



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