Geographical Distribution. -Throughout the Holarctic, Indo-Malayan, Australasian, African and Neotropical regions, from Arctic regions of Eurasia south to the Cape of Good Hope, and Tasmania; east to Fiji and other islands of the Pacific; Madagascar; and in the New World from Arctic regions including Greenland south to Tierra del Fuego, and including the Galapagos Islands. Number of Genera. -I have examined and retained one hundred and eight)'-six genera, divided among twelve subfamilies. At least six, and perhaps more, valid genera are not represented in the British Museum.(In the first volume, containing all other Rodents, one hundred and fortyseven genera were retained, and four besides these are not represented in London.)The Family Muridae belongs according to the present classification to the Superfamily Muroidae, a group containing also four families, Muscardinidae, Lophiomyidae, Rhizomyidae, and Spalacidae, which have been dealt with in the first volume.A key to these families has already been given. Notes on the essential characters of the family Muridae have also been given in Volume I. For reference purposes, these are repeated here.Char.\cters.-Zvgomasseteric structure primitively (Deomys), nearly as in Sicistinae (Dipodidae), except that the infraorbital foramen is more generalized, less enlarged, and not conspicuously wider below than above.In all remaining genera the zygomatic plate is broadened and tilted upwards to a greater or lesser degree; masseter lateralis extends its line of I -Living Rodents -II iWith reftrcnct to the cheekteeth formula of Muridae, I must note that according to some authors, the three cheekteeth represent P.4, M.i, and M.2, and it is suggested that M.3 is suppressed. There seems to be considerable evidence in favour of this view'; but for convenience throughout this work I adopt the customary notation. THE RATS FROM MADAGASCAR I'here are six genera that I have examined, containing seven well-marked species in all, from Madagascar. They are excessively difficult to classify. Most authors have referred them to a subfamily Nesomyinae, whose sole character seems to be "Habitat in Madagascar," or dumped them all in the subfamily Cricetinae. It does not seem to me possible to take either course.The sole character given by Tullberg for the group which is unusual among the Muridae he examined is the fact that the tongue possesses three papillae circumvallatae, but he only examined two genera, .Gymnuromys and Eliitrus. But this character, although in most other Muridae he examined was reduced to one, was present in Cricetomys (three); while two were present in Myospalax and Tachyoryctes. It is not a character which one can use throughout the Order; and is apparently variable in closely allied genera in other groups (for instance, Petaurista, o, Pteromys, 3, in the Pteromys group of Sciuridae). It is probably merely a primitive character which may be met with in any group.The Rats of Madagascar may be arranged as follows, in key form.Skull specialized, Microtine in aspect, with zygo...
the other genera occurring in the area being Mcsocricetiis and Phodopus. In addition to the four great subfamilies of Muridae being well represented as indicated above, there is a very interesting subfamily confined apparently to Palaearctic China and adjacent parts of Siberia only, the Myospalacinae, with one genus, Myospalax. The family Spalacidae, which is here restricted to the genus Spalax alone, is purely Palaearctic, ranging round the eastern end of the Mediterranean Sea from Hungary and the Balkan States to Egypt, and occurring in South Russia. The family Muscardinidae, represented by the typical subfamilv, is more or less western in general distribution, though represented in Japan. The four better known genera, Eliomys, Dyromvs, Glis and Muscardinus all appear to meet in Central Europe, so far as their range is concerned. Dvi'omys goes east to Tianshan and Zungaria, but not west of Central Europe; Glis ranges to Spain and the Atlantic, also east to the Caucasus and Turkestan; E/iomvs does not range east of European Russia, but occurs again in Sinai and North Africa, as well as the Iberian Peninsula;Muscardinus is not known from Spain nor east of European Russia, but ranges naturally in England and in Scandinavia, which none of the others reach except by introduction. The family Dipodidae has its headquarters in the Palaearctic.Of the more primitive groups, the Sicistinae (Sicista) has the widest range, occurring from Scandinavia, the Balkans, and Hungary, more or less across the area evidently, in suitable localities. The Chinese Eozapus represents the American subfamily Zapodinae (the only subfamily occurring in that continent). The Cardiocraniinae, containing two extremely rare types, Cardiocranius and Salpingoius, appears to be restricted to the more inaccessible parts of Chinese Central Asia, except that a species of Salpingotus is known from Afghanistan. Of the more specialized groups, the Euchoreutinae {Euc/ioreutes) is restricted to the deserts of Inner China; the Dipodinae have, however, a wide range outside Western Europe. Alhictaga and Dipus both appear to range from South Russia across much of the Asiatic portion of the area, east more or less to the North Chinese Pacific coast; Jaculus ranges across North Africa from Morocco to Egypt and east as far as Persia; and generic types worthy ot note confined to the Palaearctic with more restricted ranges are Scirtopoda, Paradipus, and Pygeretmus.The Sciuridae have, as usual, a wide distribution in the area; only in contrast to the normal element (arboreal) in tropical areas, most of the Palaearctic genera are Ground-squirrels. Citellus and Marnwta have the widest ranges, both occurring in Europe as well as much of Asia, and both occurring again in North America. Tamias, principally American, ranges in North Russia, Siberia and China. Atlantoxerus, confined to Morocco and adjacent region, represents a somewhat different type of Ground-squirrel tound chiefly in 52 DISTRIBUTION Africa, and evidently not represented in either America or the Indo-Ma...
The occurrence of vibrio disease in coalfish, cod, dab, flounders, plaice and salmon from Norwegian waters is described. A description of the pathological findings and of the bacteriological examinations carried out is given. The causative agent was found to be Yf6riu anguiliaruirz, and the reactions of these Norwegian isolates in relation to previously described biotypes of V. anguillnrum are discussed.
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