NON-INDIGENOUS BRITISH BIRDS. 187 



Breeding habits : The Smew is a nomadic migrant, 

 a bird that wanders no further south of its breeding 

 grounds than the snow and ice compel it, returning to 

 them at the first opportunity, when the south wind 

 banishes winter, towards the end of May or early in 

 June. Its favourite breeding haunts are the forest 

 districts in which the timber is of mature growth, 

 studded with lakes and swamps, and intersected by 

 streams. In winter it is more or less gregarious, but 

 during the breeding season lives in scattered pairs^ 

 probably as much because suitable nesting sites do not 

 admit of many birds incubating in company, as from 

 any inclination to breed in solitude. Of the pairing 

 habits of the Smew nothing appears to be known, but 

 probably the bird mates for life, and returns regularly 

 to one spot to breed. The nest is made either in a hole 

 in a tree trunk or a branch, or in a hollow log or stump. 

 No nest beyond a warm lining of down is prepared for 

 the eggs, the first being deposited upon the wood dust 

 at the bottom of the hole. The Smew is a close sitter, 

 but when flushed flies straight to the nearest water 

 without any demonstration. 



Range of egg colouration and measurement : 

 The eggs of the Smew were first made known to science 

 by Wolley. They were sent to him by his collector, who 

 had obtained a nest with the female bird from a hole in 

 a rotten birch trunk in Russian Lapland. Messrs. See- 

 bohm and Harvie-Brown procured others in the valley 

 of the Petchora, during the summer of 1875. They 

 are from seven to eight or nine in number, smooth in 

 texture, somewhat polished, and creamy-white in colour. 

 Average measurement, 2'c inches in length, by 1*47 inch 

 in breadth. Incubation is apparently performed by the 

 female, but the duration of the period is unknown. It is 

 possible that the male may occasionally sit upon the eggs. 



