46 ELEPHANTINE AND SEHATL. 



turesque ; from Assouan to Philse it is studded with islands, 

 which divide it into numerous channels ; and its waters, which 

 we have travelled on so smoothly for 700 miles, here become 

 tm-bulent and broken as they rush through the very narrow 

 channels, and surge over the half-sunken rocks which bar 

 their headlong course : this is the First Cataract, a series of 

 rapids extending over about three miles, from the south of the 

 island of Sehayl up to within two miles of the island of Philae. 

 The large island of Elephantine and that of Sehayl both lie 

 below the Cataract ; a few palm and sont trees are scattered 

 over them ; and the latter island is a good locality for obtain- 

 ing Crateropus acaciee, which I found breeding there in the be- 

 ginning of April. Near the most turbulent part of the rapids 

 is to be procured a Black-and- White Wagtail {Mofacilla 

 vidua) : a small colony exists here ; and the species is not to 

 be found elsewhere in Egypt. Although it has chosen so wild 

 a scene for its habitation, it is a sociable bird, frequently 

 flitting by the side of, or alighting on, the dahabeah during its 

 passage up the Cataract. There are a few other species of small 

 birds to be remarked in this neighbourhood ; on the islands 

 several kinds of Warblers are abundant, among which I 

 found Salvia Muppellii on the one opposite Philae, and 

 Sylvia melanocephala most abundant on the island of Sehayl. 

 On the mainland Saxicola Icucopijgia is plentiful, the black- 

 headed specimens being the most commonly seen, while in 

 Nubia the white-headed ones are most frequent ; but I shall 

 speak of this again in my description of the species. At 

 Assouan the two closely allied species of Desert-Lark, Ammo- 

 manes isabellina and A. fraterculus, are almost equally common, 

 this being, as it were, the southern limit of the former and the 

 northern limit of the latter ; or, more correctly, I should say, 



