Mr. R. B. Sharpens Catalogue of Accipitres. 163 



also. The iris in this specimen is noted as yellow. This 

 is the only fuliginous example I have examined in which 

 the colour of the iris has been recorded ; but I observe 

 that Von Heuglin {loc. cit.) indicates a difference of tint 

 in the irides of the two races, describing C. pectoralis as 

 " iride flavissima/^ and C. cinereus as " iride fulvescente;" 

 the irides in the type specimen of Riippell's C. funereus were 

 described by him as chestnut-brown (" kastanienbraun ") . 



I annex some notes of comparative measurements which I 

 have taken from sundry specimens of C. pectoralis and C. 

 cinereus ; these data relate to as many specimens as the 

 memoranda in my possession enable me to include in this 

 comparison : — 



inches. 



Wing in 16 specimens of C. pectoralis varies from 20-6-22*7 



„ in 8 „ C. cinereus „ „ 19*2-22"5 



Tarsus in 18 specimens of C. jjectoralis varies from 3'4- 3'7 



„ in 8 ,, C. cinereus „ „ 3"5- 4"1 



Middle toe s. u. in 18 specimens of C. pectoralis varies from. . 1'6- 2-2 



„ in 8 „ C. cinereus „ „ • ■ 1'^" 2*4 

 Culmen, exclusive of cere — 



in 10 specimens of C. pectoralis varies from 1"6- 1'7 



in 5 „ C. citiereus „ „ 1-9- 2'1 



It will be seen from the above figures that in the speci- 

 mens I have examined the measurements of the culmen in C. 

 cinereus constantly exceed those in C. pectoralis, and that 

 the same excess of size occasionally obtains also in the 

 tarsus and middle toe ; and this fact, which, to a certain ex- 

 tent, accords with the observations of Riippell and Von 

 Heuglin^, seems difficult to account for if C, pectoralis and 

 C. cinereus be really but one and the same species. 



Although Von Heuglin speaks of the transverse bars on 

 the tail as varying in different specimens of G. cinereus, 

 and although, as already noted, I have myself found theii* 

 number to be somewhat uncertain, yet the narrowness of the 

 pale bars, averaging, I think, rather less than half an inch in 



* These authors appear to regard the excess of size in the tarsus in C 

 cinereus as more constant than I have found it. 



N 2 



