OTOCOBYS BILOPHA 291 



grasses and plant stems, with a lining of a finer material. The eggs, 

 the complement of which is apparently three, are coloured with a 

 delicate apricot tinge, covered all over with rust-red and rose-violet 

 markings. Measurements about 24 X 18 mm. 



The shell of the eggs is very fine and transparent and has a dull 

 gloss. 



Dr. Koenig alludes to the habit the present species has in common 

 with some other Desert Larks, such as Ammonianes algeriensis, 

 Ammomanes cinctura, and Otocorijs bilopha, of surrounding its nest 

 with small stones. The object of this is, I think, probably a double 

 one. being partly for the better consolidation and protection of the 

 nest against wind and weather, and partly to render it less con- 

 spicuous, and more in harmony with its surroundings. Nature's 

 providential dispositions are here clearly apparent, the delicate cream 

 and pink coloration of the eggs of the above species harmonising so 

 well with the warm tints of the desert stones, and forming another 

 good illustration of adaptative and protective colouring. 



OTOCORYS BILOPHA (Temminck). 

 DESEET HORNED LARK. 



Alauda bilopha, Temm. PL Col. ill, pi. 244, fig. 1 (1823). 



Otocorys bilopha, -5^3. Consp. Avium, i, p. 246 (1850); Sharpe, Cat. 

 Birds Brit. Mus. xiii, p. 537 ; Locke, Expl. Sci. Alg. Ois. ii, p. 20 

 (1867) ; Koenig, J. /. 0. 1892, p. 389 ; Erlanger, J. f. 0. 1899, p. 455. 



Alauda (Otocorys) bilopha, Malherbe, Faune Orn. Alg. p. 21 (1855). 



Description. — Adult male, early spring, from Metlaoui, South Tunisia. 



Forehead and broad superciliary stripe white ; front part of crown and 

 two long tufts extending backward from it jet-black ; top of crown imme- 

 diately behind the black part whitish ; remainder of crown and upper parts 

 generally isabelline, rather more rufous on the upper wing-coverts and 

 secondaries ; primaries blackish-brown, the outermost feather with its 

 outer web white, the rest with their outer webs rufescent ; central rectrices 

 rufescent, the rest black, the outermost pair with the outer web white ; 

 lores and forepart of ear-coverts jet-black ; hind part of ear-coverts white ; 

 chin, upper throat and sides of neck white ; a pectoral gorget jet-black ; 



