li m. W. L. Sclatcr on the 



taken from this nest is white, tliickly marked with blood- 

 coloured spots, principally round the thinner end, and 

 measures 3*70 hy 2*75 inches. 



12. Petrochelidon spilodera. (South African Cliff 

 Swallow.) 



These Swallows last year had a colony of nests under the 

 eaves of the Dutch Reformed Church. After minruting for 

 the winter they returned last night, and their cheerful 

 twittering broke the dawn this morning (August 27th, 1905) 

 for the first time. 



^\.— Tlte Mlfiratlon of Birdii in South Africa. (A Paper 

 read before Section D of the British Association during 

 its Meeting in Johannesburg in 1905.) P)y W. L. Sclater, 

 M.A., F.Z.S., Director of the South African Museum, 

 Cape Town. 



The subject on which I propose to address you has attracted, 

 especially of late years, a very large amount of attention in 

 Europe and North America, and not only have very large 

 numbers of observations on the subject been made and re- 

 corded, but these have formed the basis for several general 

 theories of migration, which, if they are correct, should hold 

 good for the Southern Hemisphere as well as the Northern. 



The study of the migration of birds has, so far as South 

 Africa is concerned, been hitherto almost entirely neglected, 

 and until we have more observations on the times of the 

 arrival and de[)arture of our migrants, and as to their 

 presence and absence in diti'erent months of the year, it is 

 impossible to give any very reasonable account of the matter. 

 In the present paper I propose to direct your attention to 

 what is at present known with any certainty, and to point 

 out to you the lines on which a further advance may be 

 made through the co-operation of simultaneous observations 

 over a wide area. 



One of the greatest difficulties in regard to observation is 

 the lack of knowledge amongst most jxiople in Suuth Africa 



