422 LETTERS TO THE EDITOR. 



Iii short, A. minuta almost not varying by age, always brown ; 

 the old only with much much larger pens ( ? feathers) on the 

 lower parts than the young. 



A. pennnta. — Young all brown, with nice difference (but 

 slightly differing?) from the preceding; but old with light breast 

 and white belly ; most varying by age. 



A. guttata, Brm., {A. albipectus, Sev.) at every age white or 

 whitish on the lower parts; almost not varying by age in its 

 ground colour, but varying by age in its markings very like 

 A. pennata. 



Are these races or allied species ? Opinions may differ, but, 

 even if races, they deserve particular names, and must not 

 be confounded. 



5, 6, 7. — Aquila orientalis, Cab. ; A. bifasciata, Gray (sen. A. 

 raptor, Afr., Brehm) ; A. Glitschii, Sev., are again co-allied 

 but distinct forms, much varying all the three ; I am not quite 

 settled about them, and cannot yet write succinctly. They are 

 curious, as is the whole difficult group Morphnaetos, nob, 

 (A. imperialism Adalberti, orientalis, bifasciata, Glitschii, rapax, 

 fnlvescens, clanga, ncevia, 8fc.) for illustrating Darwin's theory : 

 species in different stages of their formation and separation, 

 and require an elaborate monography. Pray describe accu- 

 rately in your new work the specimens of bifasciata, Gray, 

 punctata, Gray, fulvescens, Gray, of different ages which you 

 have observed ; from your notes on Henderson's birds I see that 

 you must have large sub-Himalayan collections, I have not yet 

 compared all my specimens, the greater part being just now 

 brought from Tashkent, where I left them in a former expedition. 



8. — I mistook some Turkestan (Russian) Kites with blackish 

 ear feathers for the true Milvus govinda. My specimens are 

 M. ater. 



Milvus glaucopus, Eversm., differs thus from niger : Junior 

 pedibus albo-glaucescentibus, striis scapalibus infra latis, pallidis 

 dilute fulvis, distinctissimis ; I shot two such, but saw nothing 

 corresponding among the old ; it is a rare individual variety. 



9. — My Astur {Micronisus) cenchro'ides is the pale Cabul and 

 Punjab race of A. badius ; these Cabul specimens, which I 

 saw at Berlin, and compared with mine from the vicinity of 

 Tashkent, being intermediate between the Turkestan A. cench- 

 roides and the true Bengal A. badius, somewhat smaller than 

 the first of them. Yet is the A. badius of Punjab identical with 

 the Bengal one? The Punjab form connects still more my 

 cenchroides with the African A. sphenurus. My A. brevipes 

 figured by Sharpe and Dresser, is certainly distinct from badius 

 and cenchro'ides. 



10. — My Falco Tschernia'ievi is a larger and less brilliantly 

 coloured northern race of F. babylonicus, Gurney. 



