332 Dr. R. B. Sharpe on Birds 



but with white shoulder-patch, rump, aud abdomen ; outer 

 tail-feather on each side white. Tl>e crown is dull slate- 

 coloured mottled with black centres to the feathers. 



/. J ad. Deelfontein, Nov. 24, 1902. " With nest and 

 three eggs." 



A dark grey bird with ashy whitish abdomen. It is in much 

 worn plumage and therefore appears black in the centre of 

 the back, and mottled with black on the under surface where 

 the grey margins to the feathers have worn off. The 

 shoulder-patch is ashy grey, inclining to dull whitish on the 

 inner median coverts. 



The most curious feature of this bird is that it has not 

 white outer tail-feathers, but has the outermost rectrices 

 tipped with black like those of a young bird ! The eggs are 

 pale blue, with faint lilac spots, clots, and streaks, clustering 

 chiefly round the larger end, where they form a zone. 

 Axis 0"9-10 inch, diam. 0'65. 



(/'. 3 ad. Deelfontein, Dec. 22, 1902. 

 A light grey bird in terribly worn plumage, but with the 

 outer tail-feathers pure white. 



Anyone examining this useful series of Chats, which includes 

 nestlings, moulting birds, and specimens obtained throughout 

 the year, can scarcely wonder that Mr. Seebohm believed 

 in the existence of two species, between which occurred 

 an endless number of hybrids. I prefer, however, the con- 

 clusions of Colonels Butler and Feilden and Captain Savile 

 Reid, after having tested their results by the present series. 



The difficulty in admitting so many different stages in a 

 single species once more forces itself upon our attention, 

 notwithstanding the Deelfontein series. That the young 

 birds pass from the first black plumage to a black dress with 

 white shoulders and (white or black) abdomen seems certain. 

 The head afterwards becomes a little greyer, then still more 

 grey, then light pearly grey, and in its final stages the 

 abdomen is either white or black. In the whole of this 

 series the shoulder-patch is white and not ashy, and the 

 outer tail-feathers are mostly tipped with black, not always 

 completely, while for the bird to have two entirely white outer 



