JANUARY 27 



organ. But in the bottle-tit no such explanation holds 

 good. Both sexes are furnished alike, and there is not 

 the slightest clew to a reason why this diminutive bird 

 should be equipped with tail feathers double the length 

 of those of any of its congeners. 



The nest, too, of the bottle-tit is a remarkable 

 structure ; and I, like many other people who are not 

 careful to observe for themselves, used to imagine that 

 its bottle shape was designed to accommodate the long 

 tail of the parent bird, just as civilised man carries 

 a box of peculiar shape to carry his monstrous head- 

 gear. See how vain it is to speculate on such matters ! 

 I have never been lucky enough to see the parent bird 

 sitting on her eggs, but I am told by those who have 

 done so that she sits with her tail sticking out of the 

 front door. What, then, is the object of the deep 

 purse-like nest, with its thick sides of warm material ? 

 One would say that it was intended to keep up tempera- 

 ture during incubation. The tiny body of the mother, 

 not much more substantial than that of one of the 

 large hawk-moths, could not replace the heat escaping 

 from an open nest ; indeed, it is wonderful how it can 

 supply enough to hatch the large number of eggs, 

 sometimes from ten to eighteen. But, then, if that 

 be the purpose, how comes it that the gold-crested 

 wren, a creature no bigger than a bottle-tit, has never 

 invented a lid to the cup-shaped nest in which it rears 

 its young ? In habits, as well as in appearance, there 

 is a great difference from other tits in the longtailed 

 tit, or, if you prefer it, the mufflin, bottle-tit, poke- 



