_Rostrum longitudine capitis, rectum, forte, compressum, abruptè deflexum, emarginatum; tomiis rectis integris; naribus basalibus, lateralibus, rotundis, patulis; rictu pilis rigidiusculis obsesso. Alæ mediocres, remige primâ longâ, tertiâ, quartâque æqualibus, longissimis. Cauda mediocris, quadrata. Tarsi longi, fortes, squamis crassis annulati; digito ungueque postico mediano breviore, lateralibus æqualibus, liberis._ Mr. Gould observes that the members of this genus are remarkable for their robust form and for their strength and magnitude of their bills; and their habits strictly accord with their structure, as they are fierce and courageous. The species are closely allied to those of the preceding genus.[10] 1. AGRIORNIS GUTTURALIS. _Gould._ Tyrannus gutturalis, _Eyd. & Gerv._ Voyage de la Fav. Ois. dans Mag. de Zool. 1836. pl. 11. Pepoaza gutturalis, _D’Orb. & Lafr._ Mag. de Zool. 1837. p. 64. My specimens were obtained near Valparaiso in Chile. I saw it as far north as the valley of Copiapó. I was assured by the inhabitants that it is a very fierce bird, and that it will attack and kill the young of other birds. 2. AGRIORNIS STRIATUS. _Gould._ _A. Fæm. intensè olivaceo-brunnea; alis caudâque fuscis, utriusque plumis marginibus apiceque pallidè brunneis; rectricum externarum pogoniâ externâ albâ; gutture facieque lateribus albis, his nigrostriatis; pectore hypochondriisque olivaceo-brunneis; ventre crissoque flavescentibus._ Long. tot. 10 unc.; _alæ_, 4⁹⁄₁₂; _caudæ_, 4³⁄₁₂; _tarsi_, 1³⁄₁₂; _rostri_, 1²⁄₁₂. Head, and all the upper surface dark olive brown; wings and tail dark brown, each feather margined and tipped with pale brown, and the outer web of the external tail-feather, white; throat, and sides of the face, white, striated with black; breast and flanks olive brown; centre of the abdomen and under tail-coverts, buff; bill, horn colour; feet, black. [Illustration: _Birds. Pl. 12._ _Agriornis micropterus._ ] [Illustration: _Birds. Pl. 13._ _Agriornis leucurus._ ] Habitat, Santa Cruz, Patagonia. (_April._) I am not aware of any difference in habits between this species, and the following (_A. micropterus_); and the country inhabited by it is similar. From these circumstances I am induced to suspect, that it is the same species in an immature state. 3. AGRIORNIS MICROPTERUS. _Gould._ PLATE XII. _M. pallidè brunneus, subtus flavescenti-albus; alarum caudæque plumis griseo-marginatis; gutturis albis, brunneo-marginatis._ Long. tot. 9³⁄₁₂ unc.; _alæ_, 4⅓; _caudæ_, 2⅞; _tarsi_, 1³⁄₁₂; _rostri_, 1⅜.