SYNALLAXIS SULPHUEIFERA. 185 



cation it also comes nearest to that species. The nest is a large struc- 

 ture of sticks, eighteen inches to two feet long, placed upright among 

 the twigs at the summit of a hush. From the top where the entrance 

 is placed, a winding passage leads down to the chamber at the hottom 

 of the nest ; this is lined with soft dry grass and feathers, and four 

 pure white eggs are laid. 



201. SYNALLAXIS SULPHUBIFERA, Burm. 

 (YELLOW-MARKED SPINE-TAIL.) 



Synallaxis sulphurifera, Hudson, P. Z. S. 1872, p. 544 (Rio Negro) ; Scl. et 

 Salv. Nomencl. p. 64 ; Scl. P. Z. S. 1874, p. 24 j Durnfvrd, Ibis, 1877, p. 180, et 

 1878, p. 61 (Buenos Ayres); Barrows, Bull. Nutt. Orn. Cl. viii. p. 208 

 (Entrerios). 



Description. Above brown, slightly olivaceous ; wings blackish ; lesser wing- 

 coverts, margins of the feathers of the greater wing-coverts, and outer webs of 

 the basal halves of the wing-feathers pale chestnut; tail-feathers chestnut- 

 brown, ends much elongated and pointed ; beneath white, throat and breast 

 mottled with grey, spot in middle of throat sulphur-yellow ; flanks washed with 

 brown ; bend of wing and under wing-coverts fulvous ; bill and feet pale horn- 

 colour : whole length 6-3 inches, wing 2*1, tail 3*0. Female similar. 



Hab. South Argentina and Patagonia. 



I have found this Synallaxis, which was first described by Prof. 

 Burmeister, from specimens obtained near Buenos Ayres, in the 

 swamps along the Plata river ; also on the Rio Negro, in Patagonia, 

 where, however, it is very scarce. It inhabits the dense rush-beds 

 growing in the water, where the Limnornis curvirostris is also found. 

 It closely resembles that species in habits and language, and also assimi- 

 lates to it in colour and in the rather long, curved beak, sharp claws, 

 stout body, and short stiff tail. It is stationary, pairs for life, and 

 lives always closely concealed in its chosen bed of close-growing 

 rushes. When a person approaches their hiding-place the two birds 

 creep up to the summit of the rushes, protesting in peculiar, loud, 

 angry rattling notes. The Limnornis, which also pairs for life, has 

 precisely the same habit. 



Durnford describes the nest, found in a rush-bed, as a circular or 

 domed structure of grass, with the aperture at the side ; the eggs white. 



