1889.] NATURAL SCIENCES OF PHILADELPHIA. 79 



P. axillaris Shelly (Proc. Zool. Soc, 1884, p. 556), from Mt. 

 Kilimanjaro, seems closely allied to P. sybilla, but differs from it in 

 its larger size, black axillaries, and in the diminution of the white 

 on the inner edge of the secondaries beneath. 



It may be that a series of Gaboon specimens may show some dis- 

 tinctive race characters, but certainly the form does not differ spe- 

 cifically from the Madagascar bird, and perhaps P. axillaris may fall 

 under the same head. 



In that case P. sybilla would be considered as ranging across all 

 central Africa, P. salax representing the western face, typical P. 

 sybilla the Madagascar race and P. axillaris a mountain form of the 

 same ; while on the south the species would be replaced by P. tor- 

 quata. 



All the species just mentioned including the white-tailed species 

 P. hemprichii, may be distinguished from the group consisting of 

 P. rubicola, P. maura and P. leucura, by the color of the breast in 

 the males which in the former is dark chestnut and in the latter 

 lighter, orange rufous. 



This difference in coloration of the breast seems to correspond 

 with the geographical distribution, the lighter forms being found in 

 Europe and Asia, while the darker are confined to Africa. 



The identirication of P. salax Verr. with P. sybilla Linn., leaves the 

 bird described as P. salax in Sharpe's catalogue without a name. 

 Although the species is apparently distinct from any described form, 

 nevertheless, as there are no specimens in the Academy collection, 

 and as I have never had an opportunity of examining any, I hesitate 

 to propose a name for it and thereby, perhaps, add to the already 

 complicated synonymy of the genus. The species forming the 

 P. rubicola group to which P. sybilla belongs may be arranged 

 as follows : 



Eur. Asiatic Group. Breast orange rufous : — 

 Ao white visible on the tail. 



P. rubicola (Linn.) 



Europe and Western Asia. 



P. maura (Pall) (=P. indica, Blyth.) 



Asia ; range coalescing with that of the former somewhere 

 in the water shed of the Volga (Sharpe.) Several geo- 

 graphical races of this species have been described, but 

 do not seem worthy of specific rank. 



