Volume I Part 37 (1/2)

The beak is longer and more curved, the claws more crooked, and the tail stiffer than in other _Synallaxes_, and this difference in structure corresponds to a different mode of life. The Striped Spine-tail creeps on the trunk and larger branches of trees, seeking its insect-food in the crevices of the bark, and when seen clinging to the trunk, supported by its tail in a vertical position, with head thrown far back, and progressing upwards by short quick hops, it looks wonderfully like a small _Picolaptes_ with shortened beak. It is very restless, and while searching for insects constantly utters a short, trilling, querulous-sounding note.

It builds an open nest in the fork of a branch, of soft gra.s.ses and hair, thickly lined with feathers, and lays four or five pure white eggs.

198. SYNALLAXIs...o...b..GNII, Reichenb.

(D'ORBIGNY'S SPINE-TAIL.)

+Synallaxis...o...b..gnii+, _Scl. et Salv. Nomencl._ p. 64; _Scl. P. Z.

S._ 1874, p. 22, et 1879, p. 461; _Salvin, Ibis_, 1880, p. 358 (Salta). +Synallaxis humicola+, _Burm. La-Plata Reise_, ii. p.

468 (Mendoza, Parana). +Synallaxis cra.s.sirostris+, _Leybold, J.

f. O._ 1865, p. 401. +Synallaxis flavigularis+, _Doring, Exp. al Rio Negro, Zool._ p. 45.

_Description._--Above pale earthy brown, superciliaries whitish; wing-feathers blackish, the basal part of the secondaries pale chestnut, forming a transverse band; four middle tail-feathers blackish, the lateral pale chestnut; beneath whitish brown; middle of throat pale rufous; under wing-coverts fulvous; bill and feet horn-colour: whole length 65 inches, wing 22, tail 32.

_Hab._ Bolivia and Argentina.

This Spine-tail has been noticed by various observers in Northern Argentina, and, if we are correct in referring _S. flavigularis_ of Doring to the same species, occurs also in the Rio Negro district.

199. SYNALLAXIS MODESTA, Eyton.

(MODEST SPINE-TAIL.)

+Synallaxis modesta+, _Scl. et Salv. Nomencl._ p. 64; _Scl. P.

Z. S._ 1872, p. 544 (Rio Negro), et 1874, p. 23. +Synallaxis flavogularis+, _Burm. La-Plata Reise_, ii. p. 468 (Mendoza).

_Description._--Above earthy brown, superciliaries whitish; wings blackish, the basal half of secondaries pale clear brown, forming a transverse bar; tail black, the outer webs of all the rectrices pale chestnut; beneath whitish brown, with a large fulvous spot on the throat; under wing-coverts fulvous; bill and feet pale brown: whole length 60 inches, wing 24, tail 25. _Female_ similar.

_Hab._ Argentina, Patagonia, Chili.

This species so closely resembles the following in size and dull earthy-brown colour, that where seen in the thickets it is impossible to distinguish them. In habits they also seem alike; but this bird is, I think, less retiring, for I have seen it a.s.sociating with other species of _Synallaxis_.

On comparing specimens together, however, it is easy to separate the present bird from _S. sordida_ by noticing the colour of the external rectrices, which are black, externally edged with rufous, instead of being wholly rufous.

200. SYNALLAXIS SORDIDA, Less.

(SORDID SPINE-TAIL.)

+Synallaxis sordida+, _Hudson, P. Z. S._ 1872, p. 543 (Rio Negro); _Scl. et Salv. Nomencl._ p. 64; _Scl. P. Z. S._ 1874, p. 23; _Durnford, Ibis_, 1878, p. 396 (Centr. Patagonia); _White, P. Z.

S._ 1883, p. 39 (Cordova); _Barrows, Bull. Nutt. Orn. Cl._ viii.

p. 208 (Entrerios).

_Description._--Above earthy brown; wing-feathers blackish brown, their basal parts pale chestnut-brown, forming a transverse bar; tail blackish, the three outer rectrices and outer web of the fourth rectrix on each side wholly pale chestnut-brown; beneath pale earthy brown, clearer on the belly, and with a bright fulvous spot on the throat; under wing-coverts pale cinnamomeous; bill and feet blackish: whole length 65 inches, wing 23, tail 28. _Female_ similar.

_Hab._ Patagonia and East Argentina.

This species, which, on close comparison, is at once distinguishable from _S. modesta_ by the absence of any black colour on the three exterior pairs of tail-feathers, ranges from the extreme north of the Argentine Republic to Patagonia, where it is quite common, and is invariably found in dry situations abounding in th.o.r.n.y vegetation.