A single skin of this species was obtained at Conchitas by Hudson. Durnford also found it rather rare in Chupat and its vicinity, though resident and breeding in that district. "When flushed it never flies very far, but seeks the shelter of a small bush, squatting flat on the ground, and from its peculiar zigzag mode of flight it is difficult for the eye to follow it." 246. HYDROPSALIS FURCIFERA (Vieill.). (FORK-TAILED GOATSUCKER.) [Plate XII.] [Illustration: HYDROPSALIS FURCIFERA.] +Hydropsalis furcifera+, _Scl. et Salv. Nomencl._ p. 96; _Durnford, Ibis_, 1877, p. 185 (Buenos Ayres); _Barrows, Auk_, 1884, p. 24 (Entrerios). +Hydropsalis psalurus+, _Burm. La-Plata Reise_, ii. p. 450 (Paraná). +Hydropsalis torquata+, _Lee, Ibis_, 1873, p. 134 (Gualeguaychú). _Description._--Above brown varied with black; a light rufous collar on the back of the neck; wing-coverts with numerous rounded white or fulvous spots; wings black, crossed beneath by pale rufous bands; outer primary edged with white: beneath paler, with a pale fulvous throat-collar; tail with the outer rectrix twice as long as the middle pair, black, edged with white; the next three pairs similar, but gradually diminishing in length; the middle pair like the back, and rather longer than the second pair: whole length 20·0 inches, wing 7·2, tail 15·5. _Female_ similar, but tail short, black banded with fulvous, and without any white. _Hab._ Paraguay and Argentina. This remarkable Goatsucker was often observed by Durnford in the province of Buenos Ayres in spring and autumn. It lives on the ground, generally in damp situations, and where the grass is long and thick enough to afford some slight cover, and is generally observed in parties of four or five individuals. Its flight is noiseless, and performed by jerky erratic movements. In Entrerios Mr. Barrows tells us this species is a "rather common summer resident, arriving in August and leaving in May. While hunting capybaras and armadillos by moonlight he frequently had good opportunities for watching its movements. Its flight is nearly as irregular and as noiseless as that of a butterfly, while its beautiful tail is opened and shut in the same manner as with the Scissor-tailed Flycatcher. Alighting frequently on the ground or on stones or roots, it keeps up a continual but very soft clucking, which is the only note uttered. It was most often seen in open grassy or sandy spots in the woods, especially along the margins of the streams. By day it sits close on the ground, and if disturbed only flies a few yards, though it evidently sees well." Of its nesting-habits and eggs Mr. Barrows did not obtain any information. The figure (Plate XII.) is taken from a specimen in Sclater's collection, which was obtained at Gualeguaychú in Entrerios by Mr. Lee. 247. HELEOTHREPTUS ANOMALUS (GOULD). (SHORT-WINGED GOATSUCKER.)