Sub-family I. Thamnophilinæ.—(10 genera, 70 species.) One species of Thamnophilus inhabits La Plata; only 3 genera and 12 species are found north of Panama, the species of this sub-family being especially abundant in the Equatorial forest districts.

Sub-family II. Formicivorinæ.—(14 genera, 95 species.) Only 8 species occur north of Panama, and less than one-third of the species belong to the districts south of the Equator.

Sub-family III. Formicariinæ.—(8 genera, 46 species.) About 12 species occur north of Panama, and only 5 south of the Equatorial district.

It appears, therefore, that this extensive family is especially characteristic of that part of South America from the Amazon valley northwards.

Family 46.—PTEROPTOCHIDÆ. (8 Genera, 19 Species.)

General Distribution.
Neotropical
Sub-regions.
Nearctic
Sub-regions.
Palæarctic
Sub-regions.
Ethiopian
Sub-regions.
Oriental
Sub-regions.
Australian
Sub-regions.
1. 2 — —— — — —— — — —— — — —— — — —— — — —

The Pteroptochidæ are a group of curious Wren-like birds, almost confined to the temperate regions of South America, extending along the Andes beyond the Equator, and with a few species in South-east Brazil, and one in the valley of the Madeira. The genera are as follows:—

Scytalopus (8 sp.), Chili and West Patagonia to the Andes of Columbia; Merulaxis (1 sp.), South-east Brazil; Rhinocrypta (2 sp.), Northern Patagonia and La Plata; Lioscelis (1 sp.), Madeira valley; Pteroptochus (2 sp.), Chili; Hylactes (3 sp.), Western Patagonia and Chili; Acropternis (1 sp.), Andes of Ecuador and Columbia; Triptorhinus (1 sp.), Chili.

Family 47.—PITTIDÆ. (4 Genera, 40 Species.)

General Distribution.
Neotropical
Sub-regions.
Nearctic
Sub-regions.
Palæarctic
Sub-regions.
Ethiopian
Sub-regions.
Oriental
Sub-regions.
Australian
Sub-regions.
— — — —— — — —— — — 4— 2 — —1. 2. 3. 41. 2 — —