300 Rev. H. B. Tristram on the 



moment the female issued from another hole close by, and 

 escaped. On further search, I found a small chamber with last 

 yearns nest, and another passage out, by which the remaining 

 bird had escaped. The Arabs say that they use old snake- 

 holes, and make a second exit themselves, for security from the 

 large carnivorous lizards, which are their great enemies. The 

 retreat is always just under a bush, no doubt for the sake of 

 greater consistency in the sand, which otherwise would certainly 

 fall in and choke the inhabitants. I found new nests in process 

 of construction as early as January. The fragments of old eggs 

 which I picked up are, as might have been expected, of a blue 

 colour. There is, as will be seen from the Plate, a remarkable 

 difference in plumage between the male and female, thus refer- 

 ring it rather to Saxicola than to Dromolcea. 



37. Saxicola cenanthe. (Wheatear.) 



38. Saxicola stapazina. (Stapazine Chat.) 



39. Saxicola aurita. (Eared Chat.) 



These three Chats occur in the northern portion of the Hants 

 Plateaux, but are merely winter visitants. 



40. Saxicola lugens, Licht. S. leucomela, Temminck, 

 PI. Col. 257. (Mourning Chat.) 



This bird, in habits very like S. philothamna, but less con- 

 fined to the bushy portions of the Desert, does not appear to 

 come so far north even as the M'zab country. It dwells in the 

 boundless deserts of the Touareg, south of the furthest French 

 imaginary line. It was only here, and in the Chamba country, 

 south-west of Waregla, in lat.30° 50', that I obtained specimens. 

 It is very shy, and possesses great powers of flight. 



41. Saxicola deserti, Riipp. (Desert Chat.) 



In the general distribution of its colours this Chat very much 

 resembles the S. stapazina, but the bill and tarsi are at least half 

 as long again, and the black of the throat extends much further, 

 the rufous head and back being exchanged for a more sombre 

 isabcl colour. There is no sexual distinction of plumage. Like 

 the last-described, it is restricted to the south of the Sahara, but 

 resorts to the level, shrubless Salt-plains, hopping along the 



