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deposits in Burmah, and by two others from the Pliocene of the Nerbudda Valley; while Hippotherium—a slender, antelope-like animal, found in the Siwalik Hills and in Europe-is supposed to form a transition from the Equidæ to the Tapiridæ. These latter are found in the Upper Indus deposits, where there is a species of Tapirus, and one of an extinct genus Antelotherium. Of Rhinoceros, five extinct species have been found—in the Siwalik Hills, in Perim Island, and one at an elevation of 16,000 feet in the deserts of Thibet. Hippopotamus occurs in the Pliocene of the Nerbudda, and is represented in the older Miocene deposits by Hexaprotodon, of which three species have been found in various parts of India. Another remarkable genus, Merycopotamus, connects Hippopotamus with Anthracotherium, one of the extinct European forms allied to the swine. These last are represented by several large species of Sus, and by the extinct European genus Chorotherium.

The extinct Anoplotheridæ are represented by a species of the European genus Chalicotherium, larger than a horse.

An extinct camel, larger than the living species, was found in the Siwalik Hills.

Three species of deer (Cervus) have been found in the Siwaliks, and one in the Nerbudda deposits.

A large and a small species of giraffe (Camelopardalis) were found in the Siwalik Hills and at Perim Island.

The Bovidæ are represented by numerous species of Bos, and by the extinct genera Hemibos and Amphibos. There are also three species of antelopes, one of which is allied to the African Alcephalus.

We now come to an extraordinary group of extinct animals, probably forming a new family intermediate between the antelope and the giraffe. The Sivatherium was an enormous four-horned ruminant, larger than a rhinoceros. It had a short trunk like a tapir, the lower horns on the forehead were simple, the upper pair palmated. The Bramatherium, an allied form from Perim Island, showed somewhat more affinity for the giraffe.

Proboscidea.—No less than seven species of elephants and four

of mastodons ranged over India, their remains being found in all the deposits from the Siwalik Hills to Burmah. A large Dinotherium has also been found at Perim Island.

Reptiles.--Many remains of birds were found, but these have not been determined. Reptiles were numerous and interesting, the most remarkable being the huge tortoise, Colossochelys, whose shell was twelve feet long and head and neck eight feet more. Other small tortoises of the genera Testudo, Emys, Trionyx and Emydida were found, the Emys being a living species. There were three extinct and one living species of crocodile, and one of them was larger than any now living. The only other reptile of importance was a large lizard of the genus Varanus.

General Observations on the Miocene faunas of Europe and Asia.-Comparing the three faunas of approximately the same period, and allowing for the necessarily imperfect record of each, we find a wonderful similarity of general type over the enormous area between France on the west and the Irawaddy river in Burmah on the east. We may even extend our com. parison to Northern China, where remains of Hyæna, Tapir, Rhinoceros, Chalicotherium, and Elephas, have been recently found, closely resembling those from the Miocene or Pliocene deposits of Europe or India, and showing that the Palæarctic region had then the same great extent from west to east that it has now. Of about forty genera comprised in the Indian Miocene fauna, no less than twenty-seven inhabited Central and Western Europe during the same epoch. The Indian Miocene fossils are much what we should expect as the forerunners of the existing fauna, the giraffes and hippopotami being the only additions from the present Ethiopian fauna. The numerous forms of the restricted bovine type, show that these probably originated in India; while the monkeys appear to be altogether of Oriental types.

In Europe, however, we meet with a totally different assemblage of animals from those that form the existing fauna. We find apes and monkeys, many large Felidæ, numerous civets

and hyænas, tapirs, rhinoceros, hippopotamus, elephants, giraffes, and antelopes, such as now characterise the tropics of Africa and Asia. Along with these we meet with less familiar types, showing relations with the Centetidæ of Madagascar, the Tupaiide of the Malay Islands, the Capromys, of the West Indies, and the Echimys of South America. And besides all these living types we have a host of extinct forms,—ten or twelve genera allied to swine; nine genera of tapir-like animals; four of horses; nine of wolves; with many distinct forms of the long-extinct families of Anoplotheridæ, Xiphodontidæ, and the edentate Macrotheridæ. It is almost certain that during the Miocene period Europe was not only far richer than it is now in the higher forms of life, but not improbably richer than any part of the globe now is, not excepting tropical Africa and tropical Asia.

EOCENE PERIOD.

The deposits of Eocene age are less numerous, and spread over a far more limited area, than those of the Miocene period, and only restricted portions of them furnish any remains of land animals. Our knowledge of the Eocene mammalian fauna is therefore very imperfect and will not occupy us long, as most of the new types it furnishes are of more interest to the zoologist than to the student of distribution. Some of the Eocene mammalia of Europe are, however, of interest in comparison with those of North America of the same age ; while others show that ancestral types of groups now confined to Australia or to South America, then inhabited Europe.

Primates. The only undoubted Eocene examples of this order, are the Cænopithecus lemuroides from the Jura, which has points of resemblance to the South American marmosets and howlers, and also to the Lemuridæ; and a cranium recently discovered in the Department of Lot (S.W. France), undoubtedly belonging to the Lemuridæ, and which most resembles that of the West African "Potto" (Perodicticus). This discovery has led to another for it is now believed that remains formerly

referred to the Anoplotheridæ (Adapis and Aphelotherium from the Upper Eocene of Paris) were also Lemurs. Some remains from the Lower Eocene of Suffolk were at first supposed to be allied to Macacus, but were subsequently referred to the Ungulate, Hyracotherium. There is still, however, some doubt as to its true affinities.

Chiroptera.—In the Upper Eocene of Paris remains of bats have been found, so closely resembling living forms as to be referred to the genus Vespertilio.

Carnivora. The only feline remains, are those of Hyænodon in Upper Eocene of Hampshire, and Pterodon, an allied form from beds of the same age in France; with Ælurogale, found in the South of France in deposits of phosphate of lime of uncertain age, but probably belonging to this period. Viverridæ (civets) are represented by two genera, Tylodon, the size of a glutton from the Upper Eocene, and Palæonyctis, allied to Viverra, from the Middle Eocene of France. The Canidae (wolves and foxes) appear to have been the most ancient of the existing types of Carnivora, five genera being represented by Eocene remains. Of these, Galethylax and Cyotherium were small, and with the existing genus Canis are found in the Upper Eocene of France. Arctocyon, about the size of a wolf, is a very ancient and generalised form of carnivore which can not be placed in any existing family. It is found in the Lower Eocene of France, and is thus the oldest known member of the Carnivora.

Ungulata.—These are more numerous. Equidæ (horses) are represented by the Miocene Anchitherium in the Lower, and by a more ancient form, Anchilophus, in the Middle Eocene of France. Tapiride and Palæotheridæ were very numerous. Palæotherium and the allied genus Paloplotherium, were abundant in France and England in Upper Eocene times. They somewhat resembled the tapir, with affinities for the horse and rhinoceros. A new genus, Cadurcotherium, allied to the rhinoceros and equally large, has been found in the same deposits of phosphate of lime as the lemur and Ælurogale. In the Middle Eocene of both England and France are found Lophiodon allied to the tapir,

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but in some of the species reaching a larger size; Propalæotherium and Pachynolophus of smaller size and having affinities for the other genera named; and Plagiolophus, a small, slender animal which Professor Huxley thinks may have been a direct ancestor of the horse. In the Lower Eocene we meet with Coryphodon, much larger than the tapir, and armed with large canine teeth ; Pliolophus, a generalised type, allied to the tapir and horse; and Hyracotherium, a small animal from the Lower Eocene of England, remotely allied to the tapir.

Among the Artiodactyla, or even-toed ungulates, the swine are represented by several extinct genera, of moderate or small size-Acotherium, Choropotamus, Cebochoerus and Dichobune, all from the Upper and the last also from the Middle Eocene of France; but Eutelodon, from the phosphate of lime deposits is large. The Dichobune was the most generalised type, presenting the characters of many of the other genera combined, and was believed by Dr. Falconer to approach the musk-deer. The Cainotherium of the Miocene also occurs here, and an allied genus Plesiomeryx from the same deposits as Euteledon.

The Eocene Anoplotheridæ were numerous. The Anoplotherium was a two-toed, long-tailed Pachyderm, ranging from the size of a hog to that of an ass; the allied Eurytherium was four-toed; and there are one or two others of doubtful affinity. All are from the Upper Eocene of France and England.

Rodentia.—Remains referred to the genera Myoxus (dormouse) and Sciurus (squirrel) have been found in the Upper Eocene of France; as well as Plesiarctomys, an extinct genus between the marmots and squirrels. The Miocene Theridomys is also found here.

Marsupials.—The Didelphys (opossum) of Cuvier, now referred to an extinct genus Peratherium, is found in the Upper Eocene of France and England.

General Considerations on the Extinct Mammalian Fauna of Europe. - It is a curious fact that no family, and hardly a genus, of European mammalia occurs in the Pliocene deposits, without extending back also into those of Miocene age. There are, how

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