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kite (Milvus), eagle-owl (Bubo), and screech-owl (Strix); with the African secretary-bird (Serpentarius), and some extinct forms, as Palæocercus, Palæohierix and Palæetus.
Aquatic and wading birds were abundant, including numerous rails, bustards, herons, sandpipers, gulls, divers, and pelicans. There were also many ducks, some allied to the genus Dendrocygna; the Oriental genus of storks, Leptoptilus ; Ibidipodia, a remarkable form allied to Ibis and Ciconia ; Elornis, near Limosa; Pelagornis, a large bird allied to gannets and pelicans ; Hydrornis, allied to the ducks and petrels; Dolichopterus, allied to plovers. Perhaps the most interesting of these extinct birds are, however, the flamingoes, represented by forms hardly distinguishable from living species, and by one extinct genus Palælodus, which had very long toes, and probably walked on aquatic plants like the tropical jacanas.
The Miocene beds of North India have furnished few birds; the only one of geographical interest being an extinct species of ostrich, not very different from that now inhabiting Arabia.
On the whole, the birds of Europe at this period were very like those now living, with the addition of a few tropical forms. These latter were, however, perhaps more numerous and important than they appear to be, as they belong to inland and foresthaunting types, which would not be so frequently preserved as the marsh and lake-dwelling species. Taking this into consideration, the assemblage of Miocene birds accords well with what we know of the mammalian fauna. We have the same indications of a luxuriant vegetation and subtropical climate, and the same appearance of Oriental and especially of African types. Trogon is perhaps the most interesting of all the forms yet discovered, since it furnishes us with a central point whence the living trogons of Asia, Africa, and South America might have diverged.
In the Eocene we find ourselves almost wholly among extinct forms of birds. The earliest known Passerine bird is here met with, in Protornis, somewhat similar to a lark, found in the Lower Eocene of Switzerland; while another Passerine form, Palægithalus, and one allied to the nuthatch (Sitta), have been
discovered in the Upper Eocene of Paris. Picariæ of equal antiquity are found. Cryptornis, from the Paris Eocene, and Halcyornis from the Lower Eocene of the Isle of Sheppey, were both allied to kingfishers; while a form allied to Centropus a genus of cuckoos, or, as Milne-Edwards thinks, to the Madagascar Leptosomus, has been found in the Upper Eocene of France. Several Accipitres of somewhat doubtful affinities have been found in the same country; while Lithornis, from the Lower Eocene of the Isle of Sheppey, was a small vulturine bird supposed to be allied to the American group, Cathartes. Among the waders, some extinct forms of plovers have been found, and a genus (Agnopterus), allied to the flamingoes; while there are many swimming birds, such as pelicans, divers, and several extinct types of doubtful affinities. Most intersting of all is a portion of a cranium discovered in the Lower Eocene of Sheppey, and lately pronounced by Professor Owen to belong to a large Struthious bird, allied to the New Zealand Dinornis and also perhaps to the ostrich. Another gigantic bird is the Gastornis, from the Lower Eocene of Paris, which was as large as an ostrich, but which is believed to have been a generalised type, allied to wading and swimming birds as well as to the Struthiones.
Beyond this epoch we have no remains of birds in European strata till we come to the wonderful Archaeopteryx from the Upper Oolite of Bavaria; a bird of a totally new type, with a bony tail, longer than the body, each vertebra of which carried a pair of diverging feathers.
North America.-A number of bird-remains have lately been found in the rich Tertiary and Cretaceous deposits of the United States; but here, too, comparatively few are terrestrial forms. No Passerine bird has yet been found. The Picariæ are represented by Uintornis, an extinct form allied to woodpeckers, from the Eocene of Wyoming. Species of turkey (Meleagris) occur in the Post-Pliocene and as far back as the Miocene strata, showing that this interesting type is a true denizen of temperate North America. The other birds are, Accipitres; waders and aquatics of existing genera; and a number of extinct forms of the two latter orders—such as, Aletornis an Eocene wader;
Palæotringa, allied to the sandpipers, and Telmatobius to the rails, both Cretaceous; with Graculavus, allied to Graculus; Laornis allied to the swans; Hesperornis a gigantic diver; and Icthyornis a very low form, with biconcave vertebra, such as are only found in fishes and some reptiles-also from Cretaceous deposits.
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, Apyornis, 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, Dinornithide and Palapterygida, 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 a very important discovery, as it
1 Trans. Zool. Soc. of London, vol. viii. p. 381.
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 Trionys 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.
Crocodiles, allied to the three forms now characteristic of India, Africa, and America, have been found in the Eocene of our own country, and several species of Crocodilus have occurred in beds of the same age in North America.
Lizards are very ancient, many small terrestrial forms occurring in all the Tertiary deposits. A species of the genus Chamæleo is recorded from the Eocene of North America, together with several extinct genera.
Snakes were well developed in the Eocene period, where remains of several have been found which must have been from twelve to twenty feet long. An extinct species of true viper has occurred in the Miocene of France, and one of the Pythonidæ in the Miocene brown coal of Germany.
Batrachia occur but sparingly in a fossil state in the Tertiary deposits. The most remarkable is the large Salamander (Andreas) from the Upper Miocene of Switzerland, which
is allied to the Menopoma living in North America. · Species of frog (Rana), and Palæophryus an extinct genus of toads, have been found in the Miocene deposits of Germany and Switzerland.
Fresh water fish are almost unknown in the Tertiary deposits of Europe, although most of the families and some genera' of living marine fish are represented from the Eocene downwards.
ANTIQUITY OF THE GENERA OF INSECTS.
Fossil insects are far too rarely found, to aid us in our determination of difficult questions of geographical distribution; but in discussing these questions it will be important to know, whether we are to look upon the existing generic forms of insects as of great or small antiquity, compared with the higher vertebrates; and to decide this question the materials at our command are ample.
The conditions requisite for the preservation of insects in a fossil state are no doubt very local and peculiar; the result being, that it is only at long intervals in the geological record that we meet with remains of insects in a recognisable condition. None appear to have been found in the Pliocene formation; but in the Upper Miocene of Eninghen in Switzerland, associated with the wonderfully rich fossil flora, are found immense quantities of insects. Prof. Heer examined more than 5,000 specimens belonging to over 800 species, and many have been found in other localities in Switzerland ; so that more than 1,300 species of Miocene insects have now been determined. Most of the orders are represented, but the beetles (Coleoptera) are far the most abundant. Almost all belong to existing genera, and the majority of these genera now inhabit Europe, only three or four being exclusively Indian, African, or American.
In the Lower Miocene of Croatia there is another rich deposit of insects, somewhat more tropical in character, comprising large white-ants and dragon-flies differently marked from any