11. SAXICOLA, 377 



brown ; occasionally the brown on the five outside feathers on each 

 side is confijied to au oval spot on each web. Bill, legs, feet, and 

 claws black. Wing with the third, fourth, and fifth primaries 

 nearly equal and longest, second primary intermediate between 

 the sixth and seventh, bastard primary 0-8 inch. Length of wing 

 3-G inches (female 3-52 to 3'46), tail 2-6, culmen 0-68 to 0-65, tarsus 

 0-99 to O-S'J. 



The female differs from the male in having the head and nape 

 dark brown. No change apparently takes place after the autumn 

 moult in either sex. It is not known that birds of the year differ 

 from adults. Young in first plumage appear to be unknown. 



Strickland's Chat breeds in the cultivated districts of South-western 

 Turkestan, and winters in the North-west Provinces of India. 



a, b. S ad. sk. W.X.W. of Jodlipur. W. T. lilanford, Esq. [P.]. 



Saxicola leucomelsena and Saxicola monticola. 



These two South-African Chats and their intermediate forms are 

 involved in the greatest obscurity ; an examination of a large series 

 leads me to hazard the following hypothesis. The white-headed 

 form alone appears to inhabit Beuguella and Damara Laud. Further 

 south and east originally dwelt a black-headed form in Great Xa- 

 maqua Land, the Free State, the Transvaal, and Natal. This region 

 appears to have been invaded by the white-headed forms, which must 

 ha\e bred freely with, and been absorbed by, the original inhabitants, 

 so that we now find in the regions inhabited by the black-headed 

 form almost every intermediate form between the two. Curiously 

 enough the intermediate forms are on an average slightly the largest 

 birds. This maj- possibly be accounted for on the supposition that 

 the cross-breeding improved the race, or that the half-breds had 

 for some cause or other a harder struggle for existence, and the small 

 examples were gradually eliminated by natural selection. It is 

 probably a parallel case to S. j^icata and *S'. capistrata. ; but it may 

 perhaps be best to classify the intermediate forms in two groups, 

 calling those examples in wliich the head is light grey Saxicola 

 leucomelcna monticola, and those in which the head is dark grey 

 Saxicola monticola leucomehfna, though, if my theory be correct, a 

 large enough series will show not two intermediate forms only, but 

 an infinite series. 



The synonymy of the white-headed form is as follows : — 



13. Saxicola leucomelaena. 



Saxicola leueomelfcnn, 7>V;■^/^ Tnic. S. .//>. i. p. .33.5 (1822) ; Stricld. 



i.^- Sclatcr, Jard. Contr. Orn. lSo2, p. 140; Shar/ic, Cat. Afr. B. 



p. 21) (1871) ; Giiniri/, Aurl, >:■<». Ji. Dam. Ld. p. 10'.) (1872) ; ' Blan- 



ford lV Dresser, P. Z. S. 1874, p. 23:?, pi. xxxvii. fig. 2; Shurpe,ed. 



Laijard's />'. S. Afr. p. 247 (1^77, male). 

 Droniolica albipiloata, Borate, Joni. Sr. Lisb. p. lol (18G7, male). 

 Saxicola alpina, Chapman, Trav. S. Afr. ii. p. 399 (1808, male). 

 Saxicola atnioni, Tristram, Ibis, 18(39, p. 20(5; Grai/, Hand-l. B. i. 



