_South America._--The caverns of Brazil produced thirty-four species of birds, most of them referable to Brazilian genera, and many to still existing species. The most interesting were two species of American ostrich (_Rhea_), one larger than either of the living species; a large turkey-buzzard (_Cathartes_); a new species of the very isolated South American genus _Opisthocomus_; and a _Cariama_, or allied new genus. _Madagascar and the Mascarene Islands._--We have here only evidence of birds that have become extinct in the historical period or very little earlier. First we have a group of birds incapable of flight, allied to pigeons, but forming a separate family, _Dididæ_; and which, so far as we yet know, inhabited Mauritius, Rodriguez, and probably Bourbon. _Aphanapteryx_, an extinct genus of rails, inhabited Mauritius; and another genus, (_Erythromachus_), Rodriguez. A large parrot, said by Prof. Milne Edwards to be allied to _Ara_ and _Microglossus_, also inhabited Mauritius; and another allied to _Eclectus_, the island of Rodriguez. None of these have been found in Madagascar; but a gigantic Struthious bird, _Æpyornis_, forming a peculiar family distinct both from the ostriches of Africa and the _Dinornis_ of New Zealand inhabited that island; and there is reason to believe that this may have lived less than 200 years ago. _New Zealand._--A number of extinct Struthious birds, forming two families, _Dinornithidæ_ and _Palapterygidæ_, have been found in New Zealand. Some were of gigantic size. They seem allied both to the living _Apteryx_ of New Zealand and the emu of Australia. They are quite recent, and some of them have probably lived within the last few centuries. Remains of _Dinornis_ have also been found in a Post-Pliocene deposit in Queensland, N. E. Australia[5]--a very important discovery, as it {165}gives support to the theory of a great eastward extension of Australia in Tertiary times. EXTINCT TERTIARY REPTILES. These will not occupy us long, as no very great number are known, and most of them belong to a few principal forms of comparatively little geographical interest. Tortoises are perhaps the most abundant of the Tertiary reptiles. They are numerous in the Eocene and Miocene formations both in Europe and North America. The genera _Emys_ and _Trionyx_ abound in both countries, as well as in the Miocene of India. Land tortoises occur in the Eocene of North America and in the Miocene of Europe and India, where the huge _Colossochelys_, twelve feet long, has been found. In the Pliocene deposits of Switzerland the living American genus _Chelydra_ has been met with. These facts, together with the occurrence of a living _species_ in the Miocene of India, show that this order of reptiles is of great antiquity, and that most of the genera once had a wider range than now.