(515 ) 



whole sheep roasted on a spear, kouskoas, and our own provisions brought fronl 

 Batna, making up the grandest meal imaginable for us, as we had had nothing to 

 eat from before 5 a.m. to 4 p.m. Tlie rain that had threatened broke out on our 

 way home, but was no longer any liindraiice to us, and we reached Batna again 

 before dark." 



The plumages of Seebohm's (!hat have been described and figured by Dixon, 

 Koenig, and Hartert. It remains only to remark that Koeuig, on May 5, obtained 

 a male in change of plumage, and that we shot, on May \2, a male which agreed 

 in plumage absolutely with an adult female of the same date. It had no sign 

 of an ovary, hnt the right testicle was distinct, though only of the size of a 

 No. 12 shot. Another male was shot with large testicles, above grey, but 

 without any black on the throat ! 



It seems, therefore, that not all the males assume the final plumage during 

 the first year. 



104. Oenanthe deserti homochroa Tristr. 



(Saxicola deserti anct.) 



Saxicola hnmvchroa Tristram, Ibis 1859. p. 50. (Description of a female from the Tuaiaian 

 Sahara.) 



All Algerian and Tunisian birds have a warmer, more rufous tinge on the 

 upperside, than those from Nubia, whicli have a colder, less rufescent back, and a 

 distinct greyish tinge on the crown. They differ from the large eastern race, 

 0. f/eserti atrogiduHs (cf. Vog. pal. Famw i. p. 684) principally in being smaller, 

 still less greyish and lighter, and as a rule in having less pronounced white on the 

 inner webs of the ipiills. We have thus evidently to do with three, not only 

 two, races : 



1. 0. deserti homochroa : Sahara from Cape Blanco on the Atlantic coast to 

 the Libyan desert and the Natron valley near Cairo, on the left side of the Nile. 

 (The name homochroa must be used, as it hail been given to Saharan birds, though 

 Tristram was mistaken in separating the female on account of its white throat.) 



A male shot among the sand-dunes of Oumash, near Biskra, on April 10, 1908, 

 diifers from all the rest in being almost white underneath and very pale above, with 

 a grey tinge on the hindneck. It had strongly swollen testicles. 



2. O. dtserti deserti : Nubia, and probably Palestine. The names deserti and 

 ■paradoxa refer to the Nubian form, not to the one from the Libyan desert and 

 Natron valley. 



3. t). deserti atrogularis : Asia (see distribution in Vog. d. pal. Fauna i. 

 p. 684). 



O. deserti homchoroa is common in the clayey desert, as well as in the sandy 

 stretches, if there are hillocks hard enough for more or less permanent holes, in 

 which the bird can nest, or if there are slabs of hard earth, stones or bushes 

 giving sufficient shelter ; but it is absent from the driving sand-dunes. It is also 

 found on the edges of the sebcha, but is absent from the rocky mountain ranges. 



It is consequently common near Biskra, and is found all the way to Tonggourt, 

 but not in the " Souf " It was also common near Laghouat, and seen east of 

 Ghardaia, where hard-sef eggs were found on April 21. The eggs are of a beautiful 

 greenish blue, s|iotted with rufous. South of Biskra fresh eggs were found on 

 April 21. One of our skins has the wing 93 mm., but generally it is not more 

 than 88 — 90 mm. long. 



