128 Mr. C. H. B. Grant on Birds collected in Argentina , 
A swamp-loving bird, where its peculiar cracking call 
can be heard: in the Ajo district it is known as the “ Hunco 
cracker.” 
The nest is a solid structure attached to two or more 
stems of thick reeds, with entrance at the top side, the hole 
being protected by an overlapping hood ; the nest is lined 
with feathers, and three eggs appear to be the complete 
clutch. 
111. Leptasthenura platensis. 
Leptasthenura cegithaloides Scl. Cat. B. xv. p. 35 (part.) 
Arg. Orn. i. p. 177. 
Leptasthenura platensis Sharpe, Hand-1. B. iii. p. 53. 
a. S ad. Los Ynglases, Ajo. Oct. 29, 1908. 
b. S ad. „ „ 
c. $ ad. „ „ 
d. B ad. „ „ 
e. <$ ad. „ ,, 
f. B ad. ,, ,, 
Irides hazel ; bill blackish, 
Jan 18, 1909. 
Feb. 3, 1909. 
Mar. 12, 1909. 
Apr. 19, 1909. 
June 9, 1909. 
pearly at base 
of lower 
mandible; legs and toes olive-green. 
The October bird is much worn, and the January, February, 
and March birds are moulting; the April specimen, except 
for the tail, being in full feather. 
Not a common species in the Ajo district, and frequenting 
the Tala woods ; in habits it much resembles the Tits. 
112. Synallaxis frontalis. 
Synallaxis frontalis Scl. Cat. B. xv. p. 39; Chubb, Ibis, 
1910, p. 524 (Paraguay). 
a. S ad. Villa Oliva, Paraguay. Aug. 11, 1909. 
b. $ ad. Puerto Pinasco, „ Sept. 7, 1909. 
c , S ad. Pan de Azucar, Brazil. Sept. 20, 1909. 
d, e. B ? ad. Near Villa Franca, Paraguay. Nov. 6,1909. 
Irides amber; bill slate-coloured, upper mandible darker; 
legs and toes dark olive-green. 
All the specimens are shewing signs of wear, especially 
the November birds. The female taken in November was 
sitting. 
