268 ON AMMOMANES AND ISABELLINE BIRDS. 



paleness of the plumage of the Desert-Lark extends to the eggs, which 

 means to the colouring-matter belonging to them. 



It is not possible to notice all the isabelline birds, such as Saxicola 

 isahellina, the Isabelline Chat, Dresser's ' Birds of Europe ' (part xxviii. May 

 1874, p. 19), and the several species of Sand-Grouse, &c. Some are com- 

 pletely, and others only partially affected, by the colour in question. 

 Perhaps the most interesting is Caprinmlgus isahellinus, RUpp. 



C. agyptius, Licht., Shelley's ' Birds of Egypt ' (p. 175, with plate). Here 

 we have a case of double mimicry in one bird, or mimicry upon mimicry. 

 First there is the ordinary plumage, resembling C. europaiis, Linn., which 

 imitates the bark of a tree — over which comes the isabelhne hue of the desert 

 to wash that into sand. 



Among British species none is more valued than Cursorius isabeUinus, 

 Flem , now, alas ! turned into Cursorius gallicus — a sad wrench to one's 

 feelings, much like a visit to the dentist, but, I suppose, a stern necessity. 

 This is a true desert-bird ; and isabeUinus, from the colour, is very appropriate. 

 British-killed specimens fetch high prices ; but perhaps none exceeded the 

 Leverian example ; for, at the sale of the Museum, " it was purchased from 

 Fichtel, who had bought it, by that zealous naturalist Donovan, for the sum 

 of eighty-three guineas. It is now deposited in the British Museum" 

 (Shaw's ' General Zoology,' vol. xi. Aves, p. 501). , 



Doubtless this price, a strong one even in our time, secures so interesting 

 a skin the utmost care and attention. According to Montagu, Mr. William 

 Hammond, its first owner, presented it to Dr. Latham, who figured it. I 

 have not seen the bird. 



Mr. Keulemans has drawn a desert scene for this article, which at least 

 has one merit, there is no camel in it, dead or alive ! The reader must 

 endeavour kindly to enter into it : the sleepy half-closed eye of the bird, the 

 glare, the drought, &c. are placed before him. If, as I hope, he will lend 

 himself to a state of things which I cannot describe, not having been in the 

 Sahara (while probably he has, and knows it much better than I do), 

 imagination will assist both the artist and myself. 



