THE SAND-MARTIN. 515 



BREEDING-HABITS. Nests in sand and gravel pits, banks of rivers, 

 railway cuttings, etc., making a burrow 2-3 feet long. Occasionally 

 breeds in drain pipes projecting from wall, or hole in wall, sawdust 

 heaps, etc. Nest. Carelessly built of straws and freely lined 

 feathers. Eggs. Usually 4-5, sometimes 3 to 6 or 7. White, 

 without gloss. Average of 50 eggs, 17.6x12.4 mm. Breeding- 

 season. From about May 10 onward, but later in north. Double 

 brooded. 



FOOD. Insects taken on the wing ; chiefly smaller diptera but 

 undoubtedly also neuroptera. 



DISTRIBUTION. British Isles. Summer-resident. Widely distri- 

 buted, but local. In Ireland more frequent than Martin. Scarce 

 in extreme north of Scotland and O. Hebrides, rare breeder Orkneys, 

 and somewhat scarce migrant, once recorded nesting, Shetlands. 



MIGRATIONS. British Isles. -Early arrivals of summer-residents 

 begin middle of third week Mar. (early dates Mar. 13. Cardigan ; 

 Mar. 15, 1913, Cheshire) ; main arrival variable, last three days 

 March to second week April, lasting to beginning June ; no evidence 

 of passage-migration and but few birds reach northern isles. 

 Summer -residents begin to move south mid-July in Scotland and 

 early Aug. (occasionally end July) England and Wales, emigration 

 from south coast end (occasionally first week) Aug. to end third 

 week Sept. Some evidence passage-migration east coast, south of 

 Humber, end Aug. and Sept. none elsewhere. Stragglers frequent 

 to mid-Oct. (late dates, Oct. 19, 1909, S.E. Suffolk; Oct. 26, 

 1908, Monach Isles (O.K.) ; Oct. 30, 1911, Nov. 11, 1912, Sussex ; 

 Dec. 1914, Berks.). Irish summer-residents apparently arrive 

 and depart mainly by south-east coast ; no evidence of passage- 

 migration. 



DISTRIBUTION. Abroad. Europe generally from 70 north, south 

 to Tunisia and Algeria, east to Siberia, Syria, Palestine, but limits 

 not well known, also North America. Wintering in east and south 

 Africa, India, also in South America. Replaced by other forms 

 (limits in Asia imperfectly known) in Siberia, north-west India, 

 Turkestan, and Nile Valley. 



[NOTE. The AMERICAN PURPLE MARTIN, Progne subis subis (L.), said 

 to have been shot near Kingstown, Ireland, in 1840 (Yarrell, n, p. 361 ; 

 Sannders, p. 166), and the AMERICAN TREE-SWALLOW, Tachycineta bicolor 

 (Vieill.), said to have been killed at Derby in 1850, cannot be admitted.] 



