BRITISH WARBLERS 



to show something more than mere passion, but, on the 

 other hand, the negative evidence — that of the callous 

 behaviour of the males, except during the period of sexual 

 passion, of the desertion of the female by the male directly 

 the young are able to take care of themselves, of polygamy, 

 and of the replacement of a lost mate again and again in an 

 incredibly short space of time — is so strong that it precludes 

 the possibility of the existence, in at least a large majority 

 of the cases, of any feeling beyond a momentary passion. 



The nest is always placed low down amongst the bushes 

 and undergrowth, holly, elder, or bramble being favourite 

 resorts, but many other shrubs are utilised, and it is some- 

 times even suspended, after the same manner as that of the 

 Eeed- Warbler, from three nettles (Urtica clioica). In its 

 construction dead grasses of different sizes are principally 

 used, the coarser ones on the outside and the finer ones in 

 the interior, the lining being of horse-hair. The female does 

 the greater part of the building ; the male sometimes helps 

 independently, often singing when doing so, and at other 

 times follows her closely as she searches for material, or 

 watches her vigorous efforts to sever the various grasses, the 

 fixing of which grasses takes considerable time. They shape 

 the nest with their breasts by lying in it and turning round, 

 and if the male happens to be at work when the female 

 arrives, he immediately gives place to her. An inquisitive 

 Chiff-chaff sometimes comes to watch the proceedings, but 

 is immediately pursued. Outbursts of excitement are of 

 common occurrence with the male, and he then pursues the 

 female, erecting his feathers and flapping his wings. 



Directly the first egg is laid the male takes his turn in 

 sitting on the nest ; and in cold seasons, especially in the 

 mornings, the eggs are never left long exposed, one or other 

 of the birds always showing anxiety to return. Now the time 

 that they leave their eggs exposed, either previous to or during 

 incubation, appears to vary with the prevailing conditions of 

 the atmosphere. This procedure must be congenital, for how 



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