Prof. K. A. von Zittel—On the Mammata. 505 
species that, on the whole, only the fauna of the Phosphorites 
and the Bohnerze in Europe, that of the Santa-Cruz formation in 
Patagonia, and the fauna of the Sivalik Hills can come into com- 
parison with it. Among the specifically South American orders, 
the Edentates reach, in the numerous kinds of the Gravigr ada, Glypto- 
dontia, and Dasypoda, notable dimensions, and in the same way the 
Toxodonts, Typotheria and the Macrauchenide surpass most of 
their predecessors in size. But this exuberant growth and the 
extreme specialization of individual organs, which as a rule is 
associated with it, appear to have been fatal to its possessors, for 
none of the giant Hdentates, Toxodonts, Typotheria, and Macrau- 
chenidee survived the end of the Pampas formation, and with them, 
the larger migrants from the North, such as Mastodon, Machairodus, 
Equus, Hippidium, Mesoluma, Pale@olama, etc., also became extinct. 
The invasion from the North, which had already begun during the 
Araucanian period, introduced a considerable number of new Hlements 
into the South American fauna, among which may be named in the 
first rank, the Horse, various genera of Carnivora (Machairodus, 
Felis, Mephitis, Lutra, Nasua, <Arctotherium), a very doubtful 
representative of the Rhinocerotide (? Plicatodon), a considerable 
number of small Rodents of the Myomorpha group, and finally 
—Man himself. The fauna of the Pampas formation contains, 
according to Ameghino, the following genera ’:— 
MARSUPIALIA. +Plaxhaplus. ;Zulamops (N.) 
Didelphys. +2 Heterodon. Cervus (N.) 
+Dimerodon. +? Euryodon. (Furcifer) (N.) 
+Plohophorus. (Cariacus) (N.) 
EDENTATA. Dasypoda. (Blastoceras) (N.) 
Vermilinguia. Chlamydophorus. (Zpieuryceras) (N.) 
Myrmecophaga. t Dasypotherium. Antifer (N.) 
Gravigrada. +Chlamydotherium. Coassus (N.) 
+Megatherium. Tatusia. 
+ Essonodontotherium. Eutatus. PROBOSCIDIA. 
+Meoracanthus. Tolypeutes. {ALastodon (N.) 
+ Ocnopus. Xenurus. 
+Nothrotherium. Cheloniscus. TOXODONTIA. 
+ Mothropus. +Toxodon. 
+Mylodon. PERISSODACTYLA. + Dilobodon. 
+Pseudolestodon. +Equus (N.) } ? Zutrigonodon. 
+Lestodon. ;Hippidium (N.) 
+ Laniodon. +Macrauchenia. TYPOTHERIA. 
+Scelidotherium. {Diastomicodon. +Typctherium. 
+Platyonvx. Tapirus (N.) {Pachyrucos. 
+Glossotherium. t ? Plicatodon (N.) 
Glyptodontia. RODENTIA. 
+Glyptodon. ARTIODACTYLA. Hesperomys (N.) 
t Thoracophorus. Dicotyles (N.) Habrothrix (N.) 
+Hoplophorus. Auchenia (N.) Oxymicterus (N.) 
+Lomaphorus. | Mesolama (N.) Scapteromys (N.) 
+Panochthus. PT Stilauchenia (N.) Rhipidomys (N.) 
+E leutherocercus. tPaleolama (N.) Nectomys (N.) 
+Neuryurus. | Hemiauchenia (N.) Calomys (N.) 
+Deedicurus. {| Protauchenia (N.) Reithrodon (N.) 
1 The genera marked with + are extinct, those to which (N.) is affixed are of 
North American origin. 
