Mr. R. B. Sharpens Catalogue of Accipitres. 421 



between the females of N. spilogaster and the males of N. 

 fasciatus, in size as well as in general coloration. 



There is, however, a variation in the markings of the under 

 surface in specimens of N. spilogaster, to which I am desirous 

 of briefly alluding. Two distinct phases of such markings 

 occur in adult specimens, or at least in specimens which 

 are so far adult as to have passed beyond the stage of plumage 

 which characterizes this Eagle in its first year ; and one of 

 these phases is much more analogous to the character of 

 the lower portions of the plumage 'in A^'./asda^M^ than the 

 other. Thus, in some individuals the white of the underparts 

 is merely interspersed with sparse and narrow dark shaft- 

 marks, slightly more conspicuous than the corresponding 

 markings in N. fasciatus, but otherwise of a similar cha- 

 ractei', whilst in other specimens the dark markings on the 

 under surface are much more numerous and also very much 

 broader. 



Whether this difference is due to sex or to disparity of age 

 I am unable to say : the Norwich Museum possesses two 

 nearly adult females of the former type from the Zambesi, 

 and two adult males of the latter, one from the Zambesi and 

 the other from Natal; on the other hand, the specimen 

 figured on pi. 1 of Miiller's ' Oiseaux d'Afrique,^ which is there 

 stated to be a male, is represented in the less conspicuously 

 variegated plumage, resembling that of the two females pre- 

 served at Norwich. 



As Mr. Sharpe states that this species is an inhabitant of 

 '^ North-eastern Africa," it may be well to add that, so far 

 as I am aware, it has never been obtained to the north of the 

 20th degree of north latitude. 



With reference to the remaining species of this genus, N. 

 bellicosus, I may remark that the darker portions of the plu- 

 mage in the adult bird appear somewhat liable to fade ; and 

 Mr. Sharpens description seems to me to have been taken 

 from a partially faded specimen. In a very fine adult example 

 in perfect plumage, which I examined last year in the Zoolo- 

 gical Gardens at Antwerp, all the darker portions of the 

 plumage were slaty black, with the feathers of the upper 



