1 91 8.] the Birds uf the Anglo-Egyptian Sudan. 653 



Cisticola troglodytes troglodytes. 



Drymoica troglodytes Antinori, Cat. descr. Uccelli^ Mch. 

 1864, p. 38 : Djur, Bahr el Ghazal. 



Cisticola ferruginea apud. Butler, Ibis, 1908, p. 230, 1909, 

 p. 82. 



[B. coll.] 2 Chak Chak Feb. B.G. ; 1 Morigalla Feb., 



2 Kenisa summer, Mon. 

 [C. & L. coll.] 2 White Nile, 9^° N. 31^ E. (near Lake 



No), Feb. U.N. 



Cisticola troglodytes ferruginea. 



(Jisticola ferruginea Heuglin, SB. Akad. Wien, xix. 

 1856, p. 273 : Rahad river, Blue Nile [nom. nud.] ; id. 

 J. f. O. 1864., p. 259; Butler, Ibis, 1905, p. 130. 



[B. coll.] 4 Roseires Apl. July Aug., 1 Jebel Maba 

 Apl., 1 Fazogli May, Sen. 



This rufous-coloured Grass-Warbler is very distiuct specifi- 

 cally, but we find that the birds from the upper Blue Nile 

 are subspecifically distinct from those of the upper White 

 Nile and its tributaries. The birds from the first-named 

 district are very much paler on the lower surface, there is a 

 light wash of ferrugineous across the chest and along the 

 flanks leaving the throat and middle of the abdomen almost 

 pure white ; they are also larger, wing averaging ^ 52, 

 ? 47 mm. 



Birds from the upper White Nile, as well as examples 

 from the upper Welle river, collected by Boyd Alexander, 

 are much more richly suffused with ferruginous below the 

 throat and abdomen, never getting so white as the Blue 

 Nile bird. They are also distinctly smaller, wing of ^ 

 averaging 47, ? 43 ram. 



As will be seen from the references, Antinori's bird was 

 described from the Bahr el Ghazal and Heuglin-'s from the 

 Blue Nile, but we are not quite satisfied as to which of the 

 descriptions is the earliest ; as the birds are distinct this is 

 a matter of no great moment. 



