434 Rev. H. B. Tristram on the 



a special object of dislike to the Willow Wren, whose clamours 

 frequently disturb its noontide siesta. 



No other Shrike came under my observation in the winter, 

 nor did any appear to halt in the Desert on their vernal migra- 

 tion, though on our return to the coast we found that at least 

 five species had arrived from the south. 



90. HiRUNDO RUSTiCA. (Chimney Swallow.) 



A few pairs of Swallows remained all the winter in each oasis ; 

 but none of those observed were in mature plumage, and I there- 

 fore presume that it is only the younger and weaker birds who stay 

 behind. The Arabs informed me that for one swallow they have 

 in winter they have twenty in summer, and that they usually retire 

 about the end of November, returning in February. Certainly very 

 few had arrived by the end of February, though in the beginning 

 of that month I saw myriads on the wing at Biskra, which must 

 have remained for some time in that neighbourhood, as they 

 did not reappear in any considerable numbers in Tunis till the 

 beginning of March. But throughout the whole winter a few 

 were to be seen wherever there was water or marsh. The natives 

 are perfectly familiar with the fact of the migration of vast flocks 

 to the south, which all go, as they say, to Tirabuctoo, the El 

 Dorado of Arab and Swallow. 



91. CoTYLE RUPESTRis. (Rock Swallow.) 



I saw two of these birds in December in a ravine in the M'zab 

 country. 



92. CoTYLE RiPARiA. (Sand Martm.) 



A few at El Aghouat in November. They did not appear to 

 winter in the Sahara, and can only, I imagine, be stragglers 

 there at any time, as the weds and oases afford them but few 

 conveniences for nidification. 



93. Chelidon urbica. (House Martin.) 



Exactly the same remarks will apply to this bird as to the 

 Chimney Swallow. A few pairs may everywhere be seen througb- 

 out the winter, while in summer, I am told, there is not a hovel 

 without several building in the corners of the doorways, where 

 their nests may generally be seen. Those I shot were in im- 

 mature plumage. 



