316 Dr. P. L. Sclater on Hypotriorchis castanouotus. 



XXXVII. — Note on the Hypotriorchis castanonotus of 

 Dr. Heuglin. By P. L. Sclater. 



(Plate XII.) 



The series of Abyssinian birds collected by Sir William Harris 

 during his residence at Schoa^ which was formerly in the Museum 

 of the East India Company in Leadenhall Street, having been 

 transferred to the British Museum, I have been enabled, through 

 Mr. George Gray's kindness, to compare the specimen entered 

 in Horsfield and Moore's Catalogue of the East India Company's 

 Museum as " Polihierax semitorquatus " with typical examples of 

 the true Falco semitorquatus, Smith, collected in South Africa by 

 the describer of the species. In the first place I should mention 

 that the Abyssinian specimen of Sir W. Harris has not the 

 red back, which is stated by Dr. Heuglin to be found in both 

 sexes of his H. castanonotus. This point of difference, therefore, 

 which seems to be the chief ground on which Dr. Heuglin has 

 maintained the specific distinction between his bird and the 

 southern Falco semitorquatus, seems to fail entirely ; and we must 

 suppose that Dr. Heuglin is in error in stating that the male of 

 the Abyssinian bird, when adult, resembles the female in having 

 a red back, although this may be the case in young males. On 

 comparing the Abyssinian bird with the South African specimen 

 in corresponding plumage, the difi'erences which present them- 

 selves are but slight. The head and neck are of rather a darker 

 slaty-grey, the wings rather longer, and the legs generally rather 

 stronger and stouter in the Abyssinian specimen ; but the two 

 birds are otherwise so much alike, that I should much hesitate 

 in considering them as specifically distinct. The white external 

 marginations of the ends of the rectrices appear to be of about 

 the same extent in both specimens. 



The figure (PL XII.) is an exact copy of Dr. Heuglin's original 

 figure of Hypotriorchis castanonotus, which accompanied his de- 

 scription of the bird as already given in ' The Ibis ' (1860, p. 407) . 

 It represents, according to him, an adult male, two-thn-ds of the 

 natural size. Dr. Smith, in his ' Illustrations of the Zoology of 

 South Africa,' has figured the female of Polihierax semitorquatus ; 

 but this is, I believe, the first published representation of the 



