The breeding-season begins about November 1, and as many as seven or eight eggs are laid; these are dull white, very thin-shelled, elongated, and have the greatest diameter exactly equidistant from the two ends. Mr. Barrows speaks as follows of this species in Entrerios:--"An abundant and familiar bird in the neighbourhood of Concepcion through the entire year. It is commonly seen in flocks of twenty and upwards, visiting grain-fields, gardens, &c., and sometimes, if I was correctly informed, it has appeared in flocks of tens of thousands, completely stripping the grain-fields. They nest in communities, many pairs uniting in the building of a large common nest or mass of nests. I only saw these nests on two occasions, and had no opportunity of examining their structure. They were placed on high trees, and appeared from below to be simply irregular masses, six or eight feet in diameter, formed of small sticks and twigs. Where the nests are abundant the natives destroy the young by hundreds, and the 'squabs' when nearly grown are said to be very fine eating. The young are easily tamed, and may be taught to articulate a few simple words." 281. BOLBORHYNCHUS AYMARA (d'Orb.). (AYMARA PARRAKEET.) [Plate XV.] [Illustration: BOLBORHYNCHUS AYMARA.] +Conurus aymara+, _Burm. La-Plata Reise_, ii. p. 442 (Mendoza). +Bolborhynchus aymara+, _Scl. et Salv. Nomencl._ p. 113; _White, P. Z. S._ 1883, p. 40 (Cordova). +Conurus brunniceps+, _Burm. Journ. f. Orn._ 1860, p. 243. _Description._--Above green; head earthy brown: beneath pale grey, nearly white on the sides of the head; under wing-coverts, flanks, lower belly, and crissum pale green; under surface of wings and tail blackish; beak whitish: whole length 7·0 inches, wing 3·9, tail 4·0. _Female_ similar. _Hab._ Bolivia and N. Argentina. Prof. Burmeister found this Parrakeet not uncommon on the borders of the sierra near Mendoza. White met with it near Cosquin in the province of Cordova, in flocks on the mountain-tops, about 3500 feet above the sea-level. He says it is called "_Catita de las sierras_," and that it never descends to the valleys. Its flight is very swift, and is accompanied by a sort of chirping. The figure (Plate XV.) is taken from a specimen in Sclater's collection, obtained by Buckley in Bolivia. 282. BOLBORHYNCHUS RUBRIROSTRIS (Burm.). (RED-BILLED PARRAKEET.) +Conurus rubrirostris+, _Burm. La-Plata Reise_, ii. p. 442; _id. P. Z. S._ 1878, p. 77. +Bolborhynchus rubrirostris+, _Scl. et Salv. Nomencl._ p. 113. _Description._--Uniform green; wing-feathers blackish, edged with blue; bill rosy red: whole length 7·0 inches, wing 5·0, tail 2·8. _Hab._ Argentina. Prof. Burmeister discovered this little Parrot, of which we have never seen specimens, in the ravines of the Sierra of Uspallata, and also met with it in the Sierra of Cordova. It lives in small flocks, which fly away screaming when approached.