PRELIMINARY CLASSIFIED NOTES 279 



are sometimes recorded from the east coast of Great Britain also (cf. Nelson, 

 B. of Yorks., 1907, p. 121), and that it is a straggler to the northern isles. As 

 evidence of occasional overseas migration, we may cite the case of an example 

 obtained on Fair Isle (Shetlands) on December 27, 1906, which was referred by 

 Mr. Eagle Clarke to "the Continental race" (cf. Annals Scot. Nat. Hist., 1907, 

 p. 72). [A. L. T.] 



4. Nest and Eggs. The typical site is between a loose piece of bark and the 

 trunk of a tree at varying heights. It is also frequently placed behind ivy stems ; 

 and occasionally in crevices of boards, holes in walls, or under eaves. The nest, 

 which is constructed by both sexes, is built of moss, roots, grasses, etc., on a founda- 

 tion of small birch twigs, and with feathers, strips of thin bark, bits of wool, catkins, 

 etc. (PI. xi.) Eggs 5 or 6, rarely 7, in number, are white, generally boldly 

 marked with dark red spots at the big end, which often form a zone. (PL C.) 

 Average size of 100 British eggs, '61 x '47 in. [15*52 x 12-09 mm.]. Laying generally 

 begins late in April or early in May. Incubation lasts for 15 days (W. Evans, 

 Ibis, 1891, p. 61), and is apparently performed by both sexes. A second brood 

 is sometimes reared. [F. c. B. j.] 



5. Food. This consists chiefly of insects, many of them economically harm- 

 ful, which are found in the crevices of the bark of trees. Seeds of various sorts 

 are sometimes taken. The young are fed by both parents on insects. [A. L. T.] 



6. Song Period. It sings more or less at all seasons, most during breeding 

 time, and least from the end of June to the end of August (C. and H. Alex- 

 ander, British Birds, i. p. 370). The frequency of its winter singing probably 

 depends upon the weather. [F. B. K.] 



The following is described in the supplementary chapter on "Rare Birds" : 

 Wall-creeper, Tichodroma muraria (Linnaeus). 



