undescribed Species of Hawk. 97 



The bird is certainly not Asiur poliocephalus of Gray^ and 

 much more nearly resembles an adult of the white-breasted 

 phase of Urospizias cdbigidaris ; it is, however, quite distinct, 

 as will appear by the measurements given below^ in which I 

 have compared it with an adult specimen (a female, as T 

 believe) of Urospizias albiguluris, as well as by certain dif- 

 ferences of coloration, Avhich I will also specify. 



Before proceeding further in my comparison of the two 

 species it may be convenient to mention that I propose to 

 call the new one Urospizias jardinei, in commemoration of 

 the collection from which it passed into that of the Norwich 

 Museum. 



The following are the comparative measurements, taken in 



inches and tenths ; — 



First Middle 



Wiug. primary. Tail. Tarsus. toe, s.u. 



V.jardinei .... H'O 00 7-80 220 1-65 



U. albiyularis . . lO'D 4-20 7-20 2-50 1-60 



Although U.jardinei is somewhat the larger bird of the 

 two, it is remarkable that it has a shorter tarsus ; and a 

 further evidence of its specific distinctness exists in the 

 greater proportionate length of its first primary. 



U.jai'dinei, like U. albigularis, is white on the under and 

 black on the upper surface, where^ however, there is some 

 difference of hue, owing to the bird having been killed whilst 

 moulting ; the new feathers in the mantle being of a full black 

 colour^ whilst the older part of the upper plumage is black 

 slightly tinged with brown. But although the coloration of 

 U.jai'dinei bears this general resemblance to that of U. albi- 

 gularis, the following differences exist between the two 

 species : the cheeks and ear-coverts are a decided black in 

 U.jardinei, instead of being a dark lead-colour as in U. albi- 

 gularis, and the dark colour extends somewhat lower down^ 

 with the result of the white portion of the throat being per- 

 ceptibly narrower in U. jardinei than in U. albigularis. 



In both species the inner webs of the primaries are white 

 cross-barred with blackish brown, but in U.jardinei the cross- 

 bars are less narrow than in U. albigularis and are not placed 

 so closely together ; they also extend beyond the notch in the 



SER. v. VOL. V. H 



