Among his chief systematic determinations we may mention that he refers the tinamous to the rails, because apparently of their deep " notches," but otherwise takes a view of that group more correct according to modern notions than did most of his contemporaries.
The Dromaeognathae resemble the Ratitae, and especially the genus Dromaeus, in their palatal structure, and are composed of the Tinamous (q.v.).
Next stands the order Gallinae with 4 " cohorts "; (I) Tetraonomorphae, comprising 2 families, the sand-grouse (Pterocles) and the grouse proper, among which the Central American Oreophasis finds itself; (2) Phasianomorphae, with 4 families, pheasants peacocks, turkeys, guinea fowls, partridges, quails, and hemipodes (Turnix); (3) Macronyches, the megapodes, with 2 families; (4) the Duodecimpennatae, the curassows and guans, also with 2 families; (5) the Struthioniformes, composed of the tinamous; and (6) the Subgrallatores with 2 families, one consisting of the curious South American genera Thinocorus and Attagis and the other of the sheathbill (Chionis).
Buffon and his successors saw that the Tinamous, though passing among the European colonists of South America as "Partridges," could not be associated with those birds, and Latham's step, above mentioned, was generally approved.