BIRDS. 19 



tipped with white, their bases irregularly barred with transverse marks of 

 brown and white. Under surface. — Chin, throat, breast, belly, thighs, under 

 tail-coverts, under lining of wings, and edge of shoulders perfectly white. 

 On the flanks, however, there are some brown feathers irregularly inter- 

 spersed ; and on the lower part of the breast, most of the feathers show 

 a most obscure margin of pale brown. Bill horn-colour. Cere and tarsi 

 yellow. 

 Form.— Cere and nostril as in the 31. Leucurus, but the bill not quite so 

 strong. Feathers on the sides and back of head narrow and rather stiff; 

 those on the shoulders obtusely pointed,— which character of plumage is very 

 general in this sub-family. Wing : fourth primary very little longer than 

 the third or the fifth, which are equal to each other. First primary three 

 inches shorter than the fourth or longest, and more nearly equal to the 

 sixth than to the seventh. Extremity of wing reaching to within about an 

 inch and a half of the tail. Tarsi reticulated, with four large scales at the 

 base : upper part covered with plumose feathers for about three quarters of an 

 inch below the knee ; but these feathers hang down and cover nearly half of 

 the leg. Middle toe with fifteen scales, outer ones with about nine. Claws 

 of nearly the same degree of strength, curvature and breadth as in Polyborm 

 Brasiliensis, or in 31. leucurus, but sharper than those of the latter. 



Inch. 

 Hind claw measured in straight line from 



tip to root ...... A 



Claw of middle toe, a twentieth less than that 



of the hind one. 



Inch. 



Total length 20^ 



Tail 9 



Wings when folded . . . . .15^ 



From tip of beak to anterior edge of eye . & 

 Tarsus from soles of feet to knee joint . 3^ 



Habitat, Santa Cruz, 50° S. Patagonia. (April.) 



Mr. Gould, at the time of describing this species, entertained some doubts 

 whether it might not eventually prove to be the Phalcobcenus montanus of D'Orbigny, 

 in a state of change. I have carefully compared it with the description of the 

 P. montanus, and certainly, with the exception of the one great difference of 

 31. albogularis having a white breast, whilst that part in the P. montanus is 

 black, the points of resemblance are numerous and exceedingly close. The 

 31. albogularis, appears to be rather larger, and the proportional length of the wing 

 feathers are slightly different ; the cere and tarsi are not of so bright a colour; 

 the middle toe has fifteen scales on it instead of having sixteen or seven- 

 teen. The black shades of the upper surface are pitchy, instead of having 

 an obscure metallic gloss, and the feathers of the shoulders are terminated 

 with brown, so as to form a collar, which is not represented in the figure of 



d2 



