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procyonoides), an animal confined to North China, Japan, and the Amoor Valley, and having no close allies in any other part of the globe. In the distance are some deer, a group of animals very abundant and varied in this part of the Palaearctic region. Reptiles and Amphibia.-Reptiles are scarce in North China, only four or five species of snakes, a lizard and one of the Geckotidae occurring in the country round Pekin. The genus Halys is the most characteristic form of snake, while Callophis, an oriental genus, extends to Japan. Among lizards, Plestiodon, Maybouya, Tachydromus, and Gecko reach Japan, the two latter being very characteristic of the Oriental region. Amphibia are more abundant and interesting; Hynobius, Onychodactylus, and Sieboldtia (Salamandridae) being peculiar to it, while most of the European genera are also represented. Fresh-water Fish.-Of these there are a few peculiar genera; as Plecoglossus (Salmonidae) from Japan; Achilognathus, Pseudoperilampus, Ochetobius, and Opsariichthys (Cyprinidae); and there are many other Chinese Cyprinidae belonging to the border land of the Palaearctic and Oriental regions. Insects—The butterflies of this sub-region exhibit the same mixture of tropical and temperate forms as the birds. Most of the common European genera are represented, and there are species of Parnassius in Japan and the Amoor. Isodema, a peculiar genus of Nymphalidae is found near Ningpo, just within our limits; and Sericinus, one of the most beautiful genera of Papilionidae is peculiar to North China, where four species occur, thus balancing the Thais and Doritis of Europe. The genus Zephyrus (Lycaenidae) is well represented by six species in Japan and the Amoor, against two in Europe. Papilio paris and P. bianor, magnificent insects of wholly tropical appearance, abound near Pekin, and allied forms inhabit Japan and the Amoor, as well as P. demetrius and P. alcinous belonging to the “Protenor” group of the Himalayas. Other tropical genera occurring in Japan, the Amoor, or North China are, Debis, Neope, Mycalesis, Ypthimia (Satyridae); Thaumantis (Morphidae), at Shanghae; Euripus, Neptis, Athyma (Nymphalidae); Terias (Pieridae); and the above-mentioned Papilionidae.

Coleoptera.—The beetles of Japan decidedly exhibit a mixture of tropical forms with others truly Palaearctic, and it has been with some naturalists a matter of doubt whether the southern and best known portion of the islands should not be joined to the Oriental region. An important addition to our knowledge of the insects of this country has recently been made by Mr. George Lewis, and a portion of his collections have been described by various entomologists in the Transactions of the Entomological Society of London. As the question is one of considerable interest we shall give a summary of the results fairly deducible from what is now known of the entomology of Japan; and it must be remembered that almost all our collections come from the southern districts, in what is almost a sub-tropical climate; so that if we find a considerable proportion of Palaearctic forms, we may be pretty sure that the preponderance will be much greater a little further north.

Of Carabidae Mr. Bates enumerates 244 species belonging to 84 genera, and by comparing these with the Coleoptera of a tract of about equal extent in western Europe, he concludes that there is little similarity, and that the cases of affinity to the forms of eastern tropical Asia preponderate. By comparing his genera with the distributions as given in Gemminger and Harold's Catalogue, a somewhat different result is arrived at. Leaving out the generic types altogether peculiar to Japan, and also those genera of such world-wide distribution that they afford no clear indications for our purpose, it appears that no less than twentytwo genera, containing seventy-four of the Japanese species, are either exclusively Palaearctic, Palaearctic and Nearctic, or highly characteristic of the Palaearctic region; then come thirteen genera containing eighty-seven of the species which have a very wide distribution, but are also Palaearctic : we next have seventeen genera containing twenty-four of the Japanese species which are decidedly Oriental and tropical. Here then the fair comparison is between the twenty-two genera and seventy-four species whose affinities are clearly Palaearctic or at least north temperate, and seventeen genera with twenty-four species which are Asiatic and tropical; and this seems to prove that, although South Japan (like North China) has a considerable infusion of tropical forms, there is a preponderating substratum of Palaearctic forms, which clearly indicate the true position of the islands in zoological geography. There are also a few cases of what may be called eccentric distribution; which show that Japan, like many other island-groups, has served as a kind of refuge in which dying-out forms continue to maintain themselves. These, which are worthy of notice, are as follows: Orthotrichus (1 sp.) has the only other species in Egypt; Trechichus (1 sp.) has two other species, of which one inhabits Madeira, the other the Southern United States; Perileptus (1 sp.) has two other species, of which one inhabits Bourbon, the other West Europe; and lastly, Crepidogaster (1 sp.) has the other known species in South Africa. These cases diminish the value of the indications afforded by some of the Japanese forms, whose only allies are single species in various remote parts of the Oriental region. The Staphylinidae have been described by Dr. Sharp, and his list exhibits a great preponderance of north temperate, or cosmopolitan forms, with a few which are decidedly tropical. The Pselaphidae and Scydmenidae, also described by Dr. Sharp, exhibit, according to that gentleman, “even a greater resemblance to those of North America than to those of Europe,” but he says nothing of any tropical affinities. The water-beetles are all either Palaearctic or of wide distribution. The Lucanidae (Gemm. and Har. Cat., 1868) exhibit an intermingling of Palaearctic and Oriental genera. The Cetoniidae (Gemm. and Har. Cat. 1869) show, for North China and Japan, three Oriental to two Palaearctic genera. The Buprestidae collected by Mr. Lewis have been described by Mr. Edward Saunders in the Journal of the Linnaean Society, vol. xi. p. 509. The collection consisted of thirty-six species belonging to fourteen genera. No less than thirteen of these are known also from India and the Malay Islands; nine from Europe; seven from Africa; six from America, and four from China. In six of the genera the Japanese species are said to be allied to those of the Oriental region; while in three they are allied to European forms, and in two to American. Considering the southern latitude and warm climate in which these insects were mostly collected, and the proximity to Formosa and the Malay Islands compared with the enormous distance from Europe, this shows as much Palaearctic affinity as can be expected. In the Palaearctic region the group is only plentiful in the southern parts of Europe, which is cut off by the cold plateau of Thibet from all direct communication with Japan; while in the Oriental region it everywhere abounds and is, in fact, one of the most conspicuous and dominant families of Coleoptera. The Longicorns collected by Mr. Lewis have been described by Mr. Bates in the Annals of Natural History for 1873. The number of species now known from Japan is 107, belonging to sixty-four genera. The most important genera are . Leptura, Clytanthus, Monohammus, Praometha, Ecocentrus, Glenea, and Oberea. There are twenty-one tropical genera, and seven peculiar to Japan, leaving thirty-six either Palaearctic or of very wide range. A number of the genera are Oriental and Malayan, and many characteristic European genera seem to be absent; but it is certain that not half the Japanese Longicorns are yet known, and many of these gaps will doubtless be filled up when the more northern islands are explored. The Phytophaga, described by Mr. Baly, appear to have a considerable preponderance of tropical Oriental forms. . A considerable collection of Hymenoptera formed by Mr. Lewis have been described by Mr. Frederick Smith; and exhibit the interesting result, that while the bees and wasps are decidedly of tropical and Oriental forms, the Tenthredinidae and Ichneumonidae are as decidedly Palaearctic, “the general aspect of the collection being that of a European one, only a single exotic form being found among them.” Remarks on the General Character of the Fauna of Japan From a general view of the phenomena of distribution we feel justified in placing Japan in the Palaearctic region; although some tropical groups, especially of reptiles and insects, have largely occupied its southern portions; and these same groups have in many cases spread into Northern China, beyond the

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