_Fauna of the Brazilian caves._--What we know of the Post-Pliocene period is chiefly due to the long-continued researches of Dr. Lund in the caves of Central Brazil, mostly situated in a district near the head waters of the San Francisco river in the Province of Minas Geraes. The caves are formed in limestone rocks, and are so numerous that Dr. Lund visited thousands, but only sixty contained bones in any quantity. These caves have a floor of reddish earth, often crowded with bones. In one experiment, half a cubic foot of this earth contained jaws of 400 opossums, 2,000 mice, besides remains of bats, porcupines and small birds. In another trial, the whole of the earth in a cavern was carried out for examination, amounting to 6,552 firkins; and, from a calculation made by measured samples, it was estimated to contain nearly seven millions of jaw-bones of cavies, opossums, porcupines, and mice, besides small birds, lizards, and frogs. This immense accumulation is believed to have been formed from the bodies of animals brought into the cavern by owls; and, as these are unsocial birds, the quantity found implies an {144}immense lapse of time, probably some thousands of years. More than 100 species of Mammalia, in all, were obtained in these caves. Some were living species or closely allied to such; but the majority were extinct, and a considerable number, about one-fourth, belonged to extinct genera, or genera not now inhabiting South America. Stone implements and human remains were found in several of the caves with extinct animals. The following enumeration of these remains is from the corrected list of M. Gervais. _Primates._--Extinct species of _Cebus_, _Callithrix_, and _Jacchus_--South American genera of monkeys; with an extinct genus, _Protopithecus_--an animal of large size but belonging to the American family Cebidæ. _Chiroptera._--Species belonging to the South American Phyllostomidæ, and to two South American genera of other families. _Carnivora._--Five species of _Felis_, some allied to living animals, others extinct; a species of the widespread extinct genus _Machairodus_; and a small species referred to _Cynælurus_, the genus containing the hunting leopard now found only in Africa and India. Canidæ are represented by _Canis_ and _Icticyon_ (a living Brazilian species of the latter genus), and the extinct genus _Speothos_. Mustelidæ are represented by extinct species of the South American genera _Mephitis_ and _Galictis_. Procyonidæ, by a species of _Nasua_. Ursidæ, by _Arctotherium_, a genus closely resembling, if not identical with, that containing the "spectacled bear" of Chili.