THE GREY WAGTAIL. 205 



all seasons from M. flava and subspecies, while in summer black 

 chin and throat and in winter contrast of buii ujjper-breast and 

 bright yellow under tail-coverts are distinctive. 



Field-characters. — Differs from all other British Wagtails in 

 its long tail and blue-grey colour of upper-parts. In flight, long 

 tail and sulphur-yellow belly and under tail-coverts are conspicuous. 

 Characteristic of mountain streams in breeding-season. From 

 September to March affects more sluggish lowland streams, ponds, 

 watercress beds, etc., but never seen away from water. Call-note, 

 uttered usually on the wing, is " tzit-zee " generally rej)eated 

 several times. Alarm-note at nest a plaintive " see-eet." Song 

 a babbling Swallow-like twitter. 



Breeding-habits. — Nests in hole of cliff, rocky ledge or cavity 

 in wall, occasionally on steep bank or among tree-roots, and 

 generally quite close to running water, but sometimes some distance 

 away. Nest. — Built of moss, small twigs, leaves, roots, and 

 grasses, lined hair (preferably white horsehair), and an occasional 

 feather. Eggs. — Generally 4 to 6, sometimes only 3 ; buff or 

 stone-colour, faintly marbled with greyish-brown and often a 

 dark hair-streak. Occasionally the type approaches that of the 

 Pied Wagtail, though most eggs resemble those of Yellow Wagtail, 

 but are broader oval and paler. Erythristic varieties are rare. 

 Average of 100, eggs 18.8 x 14.27 mm. Breeding-season. — Generally 

 in latter half April or beginning of May ; occasionally beginning 

 of April. In some districts a second brood in early June, but 

 in many districts single-brooded. Inciibation. — Performed by hen 

 only as a rule, but male occasionally found incubating. Period 

 about 14 days. 



Food. — Mainly insects, especially diptera, but coleoptera also 

 recorded. Small mollusca recorded by Saxby and Norgate. 



Distribution. — British Isles. — Resident. Breeds very sparingly 

 in eastern counties south of Trent and only locally in southern 

 counties east of Devon, most common in Wales, Ireland, and 

 Scotland, but scarcer in north Scotland, breeds Orkneys, but only 

 a visitor to Shetlands and 0. Hebrides. A movement from its 

 breeding-places southwards occurs in autumn. 



Distribution. — Abroad. — Europe from south Sweden to Mediter- 

 ranean countries, east to Ural. Partial migrant, apparently only 

 in small numbers south in winter to Senegambia and British East 

 Africa. Replaced bj^ a closely allied form {M. c. melanope) in north 

 Asia (in winter in tropics), and by another on Atlantic isles. (With 

 regard to the form from the Canary Islands, see Hartert, Vog. pal. 

 Fauna, i, p. 299.) 



