648 Messrs. Sclater and Mackworth-Praed on [Ibis, 



[B. coll.] 2 Fashoda Jan. Feb., 2 Malakal May, U.N. ; 

 5 Mongalla, 3 Gigging summer, 1 Keuisa Jau. Mon. ; 

 1 Chak Chak Feb., 1 Wau Apl. B.G. 



[C. & L. coll.] 27 White Nile from Renk to Lake No, 

 Jan.-Mch. U.N. 



This unfortunate bird has suffered severely at the hands 

 of ornithologists, as can be seen by the synonymy. Hartlaub 

 described it a second time believing it to be new, but 

 unfortunately gave it the same name as tliat already assigned 

 to it by Heuglin, and subsequently both he and Sharpe 

 finding out the mistake each again christened it afresh. 



We feel that the complete elucidation of the Cisticolas 

 must be reserved until it is possible to compare all the types 

 in the European museums, and that the matter must be 

 dealt with as a whole. We are therefore merely attempting 

 here to give the correct name to the Sudanese birds. 



Sclater was able before the war, through the courtesy of 

 the authorities of the Vienna Museum, to examine Heuglin's 

 types of C. marginalis or C. marginata as he afterwards 

 called it. He found them undoubtedly identical with 

 examples taken by Hawker at Kaka on the White Nile. 



This bird has a very distinct seasonal change ; those taken 

 at Malakal, Mongalla, and Gigging are in summer (rainy 

 season) dress (PI. X. fig. 1). The crown is a dusky brown 

 without or with very faint indications of stripes, the back is 

 bluish-leaden colour heavily streaked with black, the tail is 

 shorter (averaging 48 mm. against 58 mm. of birds in 

 winter dress) and is dusky brown without any rufous. The 

 individual feathers are also distinctly wider. The winter 

 birds, on the other hand (PI. X. fig. 2), have a rufous-brown 

 crown streaked with black. The ground-colour of the back 

 fulvous not leaden, and rich rufous on either side of the 

 black central area along the shafts of the tail-feathers. The 

 wings are similar in both dresses, except that the inner 

 secondaries are margined with rufous in summer instead of 

 dusky ; the tail is much longer, as can be seen in the Plate. 



We have little doubt that Cisticola slatini recently 

 described by Wettstein (Anz. Akad. Wieu, 1916, no. 13, 



