EAST COAST OF ENGLAND. 61 



Llyn Wells l.v., April 30th, various flocks of Crows to S.W. 



Newarp l.v., March 17th to April 15th, Crows on six days to W. 



Leman and Ower l.v., Feb. 18th to May 8th, Skylarks, Star- 

 lings, Titlarks, Goldcrests, E. and E.S.E. to N.W. 



Cockle L.V., Feb. 22nd to March 31st, Black Crows, Ducks, 

 Jackdaws, Starlings, Larks, Lapwings, " Snow-birds " to W. 

 On March 20th, 24th, and 26th, Black Crows or Books con- 

 tinuous from 5.50 a.m. to 11 a.m., E. to W. ; and on 31st also 

 continuous from morning to night in the same direction. 



All these entries show a great immigration to our coast from 

 the east in the spring months, and on precisely the same lines 

 and directions as are travelled by these birds in the autumn. 



An interesting feature of the autumn migration is the occur- 

 rence of a flight of the Blue-throated Warbler, Cyanecula suecica; 

 twelve altogether were obtained, all being birds of the year, and 

 nine of these on the coast of Norfolk, besides about twenty 

 others seen by competent observers. 



Very few Goldcrests, compared with the enormous flights of 

 the previous autumn, have crossed, and the same scarcity is 

 observable in the Heligoland return. Curiously enough, the 

 Hedgesparrow, Accentor modidaris, which migrated in such im- 

 mense numbers in the same autumn, has been almost entirely 

 absent. About half a dozen are recorded at Heligoland, none on 

 the East Coast of England. 



The intermittent migration of some birds, as the Jay, Shore 

 Lark, Goldcrest, Hedge-sparrow, Siskin, and Mealy Redpoll, 

 indicated by their extraordinary abundance in some years, and 

 partial or entire absence in others, is perhaps suggestive of local 

 causes influencing and regulating their movements, such as a 

 succession of favourable breeding seasons, scarcity or failure of 

 food, sudden meteorological changes ; these acting separately or in 

 combination, would be sufficient to compel the migration of large 

 bodies of birds from centres or localities, where, under normal 

 conditions, they would either have remained or some part only 

 migrated. In this manner whole districts may become denuded 

 for a time of their feathered inhabitants, and the balance become 

 again rectified by a return movement in the spring, or from the 

 surplus supply bred in other districts. 



Of the enormous immigration which crosses our east coast in 

 the autumn, either to winter in these islands or passing across 



