43 



feathers with very distinct emarginations, the fourth the longest ; 

 tibia with whole and divided scales (fig. 3). 



I give this subgenus the name of Spiziapteryx, aud the species I 

 have named 



Harpagus circumcinctus. 



Biag. — Size of the Kestril, with white stripe over the eye, which 

 encircles the whole head and is connected with a white collar ; the 

 tail-covers, above and beneath, white. 



Desc?: — Rufous ash-grey, beneath lighter, with dark brown shaft- 

 stripes ; the white stripe over the eye, and the collar black marginated ; 

 tibia-covers white ; the arm and hand wings white at the roots, and 

 like the stronger cover-feathers, with white spots and bands on the 

 inner and outer webs ; the first wing-feather without spots on the ex- 

 terior web, and with fine white spots on the interior web ; tail black- 

 brovvTi ; beneath with white roots and three small white bands and 

 an end band ; the fifth without spots on the exterior web ; the 

 fourth with only traces ; the third exhibits round white spots ; 

 and the two exterior feathers are white-banded. From this very 

 irregular distribution of spots, the tail, seen from above, exhibits a 

 very irregular drawing. Cere, naked eye region and feet yellow ; 

 nails dark brown. 



I apprehend that this specimen, the only one in England, is not a 

 very old bird. Lord Derby received this bird from Chili, by Mr. 

 Bridges. 



Dimen. — Head, 49 ; bill, from the cere, 16 ; from the gape, 22 ; 

 height, 13; breadth, 20; over wing, 1 23 ; tip of the wing, 56; middle 

 tail-feather, 148 ; outer tail-feather, 115 ; tarsus, 45 ; middle-toe, 26 ; 

 nail, 11; outer-toe, 17^; nail, 10; inner-toe, 16; nail, 12; after-toe, 

 13; nail, 13. 



A new species of the subgenus Satjrophagus, Swains. 



In the little subgenus Saurophagus, Swains., we had, till now, only 

 three species. These are, lictor, sulphuratus, and Jlavus. I received 

 by Mr. Wollweber from Zacatecas in Mexico an only specimen of a 

 fourth species ; but I found in the collection of Lord Derby, and in 

 the British Museum, a great number of the same species. 



To this species I have given the name of Derby anus, as a mark of 

 my respect for that distinguished patron of ornithological science, the 

 Earl of Derby, President of the Zoological Society. 



All the species of this little subgenus have the same general colour- 

 ing, and are distinguished only by very few characters taken from the 

 colouring of the wings and from the dimensions. The young ones 

 have, like the young birds of Scaphorhynchus, the bill shorter and 

 bigger, and the head is black, without the beautiful crest of the old 

 birds. The old birds have a white front, connected with a white 

 band over the eyes and over the black ear-covers, and surrounding 

 the black head, which in the middle is ornamented with a yellow 

 crest ; the chin and imderpart of the neck white ; breast, belly, 



