414 MR. R. B. SHARPE ON FALCO ARCTICUS. [Apr. 1, 



with white, the hairs of the body being greyish for two thirds of their 

 length, the terminal third being brownish black with a white tip. 

 Fur much less thick than in Sc. alboniger. Margins of the para- 

 chute with a very narrow and inconspicuous yellowish-white edge. 

 Paws and spur light brownish, with many yellowish hairs. Lower 

 parts rather densely covered with hair (especially the body and limbs), 

 yellowish white ; scrotum and prseanal region orange-coloured. 

 Lower side of the parachute light greyish brown. Tail bushy, con- 

 stricted near the base, brownish grey, darker along the upper and 

 lower median lines, many of the hairs being black near the tip. 



Cheeks without bristles ; ears short ; incisors of adult males pale 

 yellow. Length of the body from the nose to the vent 10 inches ; 

 of the tail 9 inches ; of the carpal spur 2 inches 1 line. 



I have seen two examples of this species, both adult males, the 

 tail of one being a little more bushy and darker than that of the 

 other. One is from Pinang, and has been presented by his Grace the 

 Duke of Argyll; the other, from Malacca, has been purchased. 



5. On the Falco arcticus of Holboll, with Remarks on the 

 changes of Plumage in some other Accipitrine Birds. 

 By R. Bowdler Sharpe, F.L.S., F.Z.S., &c v Senior 

 Assistant, Zoological Department, British Museum. 



[Eeceived March 4, 1S73.] 



(Plate XXXIX.) 



The late Governor Holboll, when in Greenland, paid evident at- 

 tiontothetwo Jer Falcons found in that country, and recognized two 

 distinct species, though he failed to assign to them thoroughly tren- 

 chant characters ; hence the difficulty in the recognition of his Falco 

 arcticus. In a paper published on the subject in the ' Zeitschrift 

 fur die gesammten Naturwissenschaften' (vol. iii. 1854, p. 425), he 

 calls these two birds Falco islandicus candicans, Schlegel, and F. 

 arcticus, Holboll. He draws up the characters of these two birds 

 not on the differences of colour, but upon certain variations in the 

 proportions of the tarsus and middle toe, &c, and in the shape of 

 the tail. These characters, if substantiated, would have relegated 

 the two Greenland Jer Falcons to different genera, a consummation 

 which would have much simplified the matter ; but unfortunately 

 no one was ever able to ratify them, and the confusion became worse 

 confounded. We possess in the Museum several birds collected in 

 Greenland by Holboll, and among them a noble seriesof the true Green- 

 land Jer Falcon (Falco candicans). On the stands of some of these 

 the late Mr. Gray has recorded (doubtless from Holboll's own tickets) 

 that they are the F. arcticus of Holboll, from which it would appear 

 that his species consisted partly of the fresh-moulted examples of 

 F. candicans (the so-called "dark race"), and partly of the "light 

 variety*' of the Iceland Falcon found in Greenland. No one, there- 



