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one to East Africa, while twenty-seven are peculiar to Palestine. It is evident therefore that an unusual number of East African birds have extended their range to this congenial district, but most of these are desert species and hardly true Ethiopians, and do not much interfere with the general Palearctic character of the whole assemblage. As an illustration of how wide-spread are many of the Palearctic forms, we may add, that seventynine species of land birds and fifty-five of water birds, are common to Palestine and Britain. The Oriental and Ethiopian genera Pycnonotus and Nectarinea are found here, while Bessornis and Dromolaa are characteristically Ethiopian. Almost all the other genera are Palearctic.

Persia is another remote region generally associated with the idea of Oriental and almost tropical forms, but which yet undoubtedly belongs to the Palearctic region. Mr. Blanford's recent collections in this country, with other interesting information, is summarised in Mr. Elwes's paper on the "Geographical Distribution of Asiatic Birds" (Proc. Zool. Soc. 1873, p. 647). No less than 127 species are found also in Europe, and thirty-seven others belong to European genera; seven are allied to birds of Central Asia or Siberia, and fifteen to those of North-East Africa, while only three are purely of Indian affinities. This shows a preponderance of nearly nine-tenths of Palearctic forms, which is fully as much as can be expected in any country near the limits of a great region.

Reptiles and Amphibia.—The climatal conditions being here more favourable to these groups, and the genera being often of limited range, we find some peculiar, and several very interesting forms. Rhinechis, a genus of Colubrine snakes, is found only in South Europe; Trogonophis, one of the Amphisbænians— curious snake-like lizards-is known only from North Africa; Psammosaurus, belonging to the water lizards (Varanidæ) is found in North Africa and North-West India; Psammodromus, a genus of Lacertidæ, is peculiar to South Europe; Hyalosaurus, belonging to the family Zonuridæ, is a lizard of especial interest, as it inhabits North Africa while its nearest ally is the Ophisaurus or "glass snake" of North America; the family of

the scinks is represented by Scincus found in North Africa and Arabia. Besides these Seps, a genus of sand lizards (Sepida) and Agama, a genus of Agamidæ, are abundant and characteristic.

Of Amphibia we have Seiranota, a genus of salamanders found only in Italy and Dalmatia; Chioglossa, in Portugal, and Geotriton, in Italy, belonging to the same family, are equally peculiar to the sub-region.

Freshwater Fish.-One of the most interesting is Tellia, a genus of Cyprinodontidæ found only in alpine pools in the Atlas mountains. Paraphoxinius, found in South-East Europe, and Chondrostoma, in Europe and Western Asia, genera of Cyprimidæ, seem almost peculiar to this sub-region.

Insects-Lepidoptera.-Two genera of butterflies, Thais and Doritis, are wholly confined to this sub-region, the former ranging over all Southern Europe, the latter confined to Eastern Europe and Asia Minor. Anthocharis and Zegris are very characteristic of it, the latter only extending into South Russia, while Danais, Charaxes, and Libythea are tropical genera unknown in other parts of Europe.

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Coleoptera. This sub-region is very rich in many groups of Coleoptera, of which a few only can be noticed here. Among Carabidæ it possesses Procerus and Procrustes, almost exclusively, while Brachinus, Cymindis, Lebia, Graphipterus, Scarites, Chlænius, Calathus, and many others, are abundant and characteristic. Among Lamellicorns-Copridæ, Glaphyridæ, Melolonthidæ, and Cetoniidæ abound. Buprestidæ are plentiful, the genera Julodis, Acmaodera, Buprestis, and Sphenoptera being characteristic. Among Malacoderms-Cebrionidæ, Lampyridæ, and Malachiidæ abound. The Tenebrioid Heteromera are very varied and abundant, and give a character to the sub-region. The Mylabridæ, Cantharidæ, and Edemeridæ are also characteristic. Of the immense number of Curculionida-Thylacites, Brachycerus, Lixus, and Acalles may be mentioned as among the most prominent. Of Longicorns there are few genera especially characteristic, but perhaps Prinobius, Purpuricenus, Hesperophanes, and Parmena are most so. Of the remaining families, we may mention Clythridæ, Hispidæ, and Cassididæ as being abundant.

The Mediterranean and Atlantic Islands.-The various islands of the Mediterranean are interesting to the student of geographical distribution as affording a few examples of local species of very restricted range, but as a rule they present us with exactly the same forms as those of the adjacent mainland.1 Their peculiarities do not, therefore, properly come within the scope of this work. The islands of the Atlantic Ocean belonging to this sub-region are, from their isolated position and the various problems they suggest, of much more interest, and their natural history has been carefully studied. We shall therefore give a short account of their peculiar features.

Of the three groups of Atlantic islands belonging to this subregion, the Canaries are nearest to the Continent, some of the islands being only about fifty miles from the coast of Africa. They are, however, separated from the mainland by a very deep channel (more than 5,000 feet), as shown on our general map. The islands extend over a length of 300 miles; they are very mountainous and wholly volcanic, and the celebrated peak of Teneriffe rises to a height of more than 12,000 feet. The small Madeira group is about 400 miles from the coast of Morocco and 600 from the southern extremity of Portugal; and there is a depth of more than 12,000 feet between it and the continent. The Azores are nearly 1,000 miles west of Lisbon. They are quite alone in mid-Atlantic, the most westerly islands being nearer Newfoundland than Europe, and are surrounded by ocean depths of from 12,000 to 18,000 feet. It will be convenient to take these islands first in order.

Azores. Considering the remoteness of this group from every other land, it is surprising to find as many as fifty-three species of birds inhabiting or visiting the Azores; and still more to

1 Malta is interesting as forming a resting-place for migratory birds, while crossing the Mediterranean. It has only eight land and three aquatic birds which are permanent residents; yet no less than 278 species have been recorded by Mr. E. A. Wright as visiting or passing over it, comprising a large proportion of the European migratory birds. The following are the permanent residents: Cerchneis tinnunculus, Strix flammea, Passer salicicola, Emberiza miliaria, Corvus monedula, Monticola cyanea, Sylvia conspicillata, Columba livia, Puffinus cinereus, P. anglorum, Thalassidroma pelagica.

find that they are of Palearctic genera and, with one exception, all of species found either in Europe, North Africa, Madeira, or the Canaries. The exception is a bullfinch peculiar to the islands, but closely allied to a European species. Of land birds there are twenty-two, belonging to twenty-one genera, all European. These genera are Cerchneis, Buteo, Asio, Strix, Turdus, Oriolus, Erithacus, Sylvia, Regulus, Saxicola, Motacilla, Plectrophanes, Fringilla, Pyrrhula, Serinus; Sturnus, Picus, Upupa, Columba, Caccabis, and Coturnix. Besides the bullfinch (Pyrrhula) other species show slight differences from their European allies, but not such as to render them more than varieties. The only truly indigenous mammal is a bat of a European species. Nine butterflies inhabit the Azores; eight of them are European species, one North American. Of beetles 212 have been collected, of which no less than 175 are European species; of the remainder, nineteen are found in the Canaries or Madeira, three in South America, while fourteen are peculiar to the islands.

Now these facts (for which we are indebted to Mr. Godman's Natural History of the Azores) are both unexpected and exceedingly instructive. In most other cases of remote Oceanic islands, a much larger proportion of the fauna is endemic, or consists of peculiar species and often of peculiar genera; as is well shown by the case of the Galapagos and Juan Fernandez, both much nearer to a continent and both containing peculiar genera and species of birds. Now we know that the cause and meaning of this difference is, that in the one case the original immigration is very remote and has never or very rarely been repeated, so that under the unchecked influence of new conditions of life the species have become modified; in the other case, either the original immigration has been recent, or if remote has been so frequently repeated that the new comers have kept up the purity of the stock, and have not allowed time for the new conditions to produce the effect we are sure they would in time produce if not counteracted. For Mr. Godinan tells us that many of the birds are modified-instancing the gold-crested wren, blackcap, and rock dove-and he adds, that the modifica

tion all tends in one direction-to produce a more sombre plumage, a greater strength of feet and legs, and a more robust bill. We further find, that four of the land-birds, including the oriole, snow-bunting, and hoopoe, are not resident birds, but straggle accidentally to the islands by stress of weather; and we are told that every year some fresh birds are seen after violent storms. Add to this the fact, that the number of species diminishes in the group as we go from east to west, and that the islands are subject to fierce and frequent storms blowing from every point of the compass, and we have all the facts requisite to enable us to understand how this remote archipelago has become stocked with animal life without ever probably being much nearer to Europe than it is now. For the islands are all volcanic, the only stratified rock that occurs being believed to be of Miocene date.

Madeira and the Canaries.-Coming next to Madeira, we find the number of genera of land birds has increased to twenty-eight, of which seventeen are identical with those of the Azores. Some of the commonest European birds-swallows, larks, sparrows, linnets, goldfinches, ravens, and partridges, are among the additions. A gold-crested warbler, Regulus Maderensis, and a pigeon, Columba Trocaz, are peculiar to Madeira.

In the Canaries we find that the birds have again very much increased, there being more than fifty genera of land birds; but the additions are wholly European in character, and almost all common European species. We find a few more peculiar species (five), while some others, including the wild canary, are common to all the Atlantic Islands or to the Canaries and Madeira. Here, too, the only indigenous mammalia are two European species of bats.

Land Shells.-The land shells of Madeira offer us an instructive contrast to the birds of the Atlantic Islands. About fiftysix species have been found in Madeira, and forty-two in the small adjacent island of Porto Santo, but only twelve are common to both, and all or almost all are distinct from their nearest allies in Europe and North Africa. Great numbers of fossil shells are also found in deposits of the Newer Pliocene period; and

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