214 Mr. R. Swinhoe on Formosan Ornithology. 



Mr. Gurney tells me that he is informed by Mr. Blyth that this 

 latter species has, in the adult form, both sexes coloured alike. In 

 the broad, flat, open country of the south-west, near Taiwanfoo, I 

 observed another Harrier, which I took to be C. cyaneus, L. ; 

 but of the species I cannot be sure, as it might have been one of 

 two cognate forms which are hai'd to distinguish from it at a 

 distance, except by a most experienced eye. These are the Pale 

 Harrier [Circus swainsonii, Smith) and the American Harrier (C 

 hudsonius, L.). The former of these has lately been procured by 

 Capt. Blakiston on the Yangtsze River ; and of the latter, speci- 

 mens may be seen in the Leyden Museum, from the Philippines 

 and Kamtschatka. 



I procured no specimens of Harriers in Formosa ; but as Mr. 

 Gurney was anxious to have the Circus spilonotus figured, I have 

 supplied a male and female, from the neighbourhood of Amoy, 

 for that purpose. With reference to this species Mr. Gurney 

 writes, " 1 have just compared three male specimens of C. 

 spilonotus with three males of C. melanoleucus, and enclose you 

 the measurements, by which you will see that C. spilonotus con- 

 siderably exceeds C. melanoleucus in all its measurements; in 

 addition to which, it has a much larger bill and stronger tarsi. 

 In all these respects (as also in some degree in colouring) it 

 approaches to an allied but still larger species, C. assimilis, 

 Gould, of Australia. I do not think that C. spilonotus ever 

 assumes the black plumage which characterizes the head, neck, 

 back, and a portion of the wings of the adult male of C. melano- 

 leucus. I have not been able to compare your female of C. spilo- 

 notus with a female of C. melanoleucus, the only (supposed) 

 female which I have of the latter being an individual of the sex 

 of which I do not feel sure. 



I have unfortunately no measurements of C. spilonotus taken 

 from birds in a fresh state. The only note I can find in my 

 journals is the following, made on a male shot at Amoy, the 27th 



