Mr. R. B. S/iarpe's (kitalogne of Accipitres. 473 



transverse bars of pale rufesceiit brown, which become broader 

 and more rufous on the flanks and on the outer side of the 

 thighs, but on the under tail-coverts are narrow, sparse, and 

 irregular. 



Mr. Sharpe does not describe the female of this species, 

 and I am unable to supply the deficiency ; but Dr. Hartlaub, 

 at p. 16 of his work on the birds of West Africa, remarks 

 respecting it, " The female does not essentially difier in colour- 

 [from the male] , but is a third larger." 



With regard to A. minuUus, it may be worth observing 

 that in two of the specimens preserved in the Norwich Mu- 

 seum, an adult male and female approaching the period of 

 moulting, the white spots on the central rectrices have evi- 

 dently become much more abraded by the action of the wea- 

 ther than the dark portions of the same feather ; and I may 

 add that I have frequently observed the same phenomenon 

 in the case of the pale spots on the tail of Faico saker. 



Another specimen of A. minuHus, in the same collection, 

 an immature female, is commencing, by a moult, the assump- 

 tion of the adult dress upon the breast, which I note as indi- 

 cative of the mode in which the change is effected in this 

 species. 



Following my purpose of referring in the first instance to 

 the more aberrant species of the genus Accipiter, I may now 

 mention a remarkable African form, A. melanoleucus , which, 

 though it has the elongated middle toe of a Sparrow- Hawk, 

 nearly approaches in size to the typical Goshawks, being not 

 much smaller than Astur palumbarius. 



The coloration of this species, especially when adult, is 

 very peculiar, and seems to point it out as naturally separated 

 from all other Hawks. 



It is found in three very distinct phases of plumage, which 

 are severally designated by Mr. Sharpe as " young," " ma- 

 ture," and ** adult," and each of which is common to both 

 sexes. 



The measurements supplied by Mr. Sharpe under the head 

 of " mature," give the ordinary dimensions of the male bird ; 

 and those under the head of " adult," those of the female. 



