Against this extensive series of characteristic groups, all either of American type or very distinct forms of Old World families, and therefore implying great antiquity, we find, in mammalia and birds, very scanty evidence of that direct affinity with the north temperate zone, on which some naturalists lay so much stress. We cannot point to a single terrestrial genus, which is characteristic of the north and reappears in this south temperate region without also occurring over much of the intervening land. _Mustela_ seems only to have reached Peru; _Lepus_ is isolated in Brazil; true _Ursus_ does not pass south of Mexico. In birds, the northern groups rarely go further south than Mexico or the Columbian Andes; and the only case of discontinuous {39}distribution we can find recorded is that of the genus of ducks, _Camptolæmus_, which has a species on the east side of North America and another in Chili and the Falkland Islands, but these, Professor Newton assures me, do not properly belong to the same genus. Out of 30 genera of land-birds collected on the Rio Negro in Patagonia, by Mr. Hudson, only four extend beyond the American continent, and the same exclusively American character applies equally to its southern extremity. No list appears to have been yet published of the land-birds of the Straits of Magellan and Tierra del Fuego. The following is compiled from the observations of Mr. Darwin, the recent voyage of Professor Cunningham, and other sources; and will be useful for comparison. TURDIDÆ. 1. Turdus falklandicus. TROGLODYTIDÆ. 2. Troglodytes magellanicus. FRINGILLIDÆ. 3. Chrysomitris barbata. *4. Phrygilus gayi. *5. " aldunatii. 6. " fruticeti. *7. " xanthogrammus. 8. Zonotrichia pileata. ICTERIDÆ. 9. Sturnella militaris. 10. Curæus aterrimus. HIRUNDINIDÆ. 11. Hirundo meyeni. TYRANNIDÆ. 12. Tænioptera pyrope. 13. Myiotheretes rufiventris. 14. Muscisaxicola mentalis. 15. Centrites niger. 16. Anæretes parulus. 17. Elainea griseogularis. DENDROCOLAPTIDÆ. 18. Upucerthia dumetoria. *19. Cinclodes patagonicus. *20. " fuscus. *21. Oxyurus spinicauda. PTEROPTOCHIDÆ. *22. Scytalopus magellanicus. PICIDÆ. *23. Campephilus magellanicus. 24. Picus lignarius. ALCEDINIDÆ. 25. Ceryle stellata. TROCHILIDÆ. 26. Eustephanus galeritus. CONURIDÆ. 27. Conurus patagonus. VULTURIDÆ. 28. Cathartes aura. 29. Sarcorhamphus gryphus. FALCONIDÆ. 30. Circus macropterus. 31. Buteo erythronotus. 32. Geranoaëtus melanolencus. 33. Accipiter chilensis. 34. Cerchneis sparverius. 35. Milvago albogularis. 36. Polyborus tharus. STRIGIDÆ. 37. Asio accipitrinus. 38. Bubo magellanicus. 39. Pholeoptynx cunicularia. 40. Glaucidium nana. 41. Syrnium rufipes. STRUTHIONIDÆ. 42. Rhea darwinii.