February 8, 1900] 



NATURE 



341 



THE ANIMALS OF BRITAIN AND THEIR 



ORIGIN. 

 The History of the European Fauna. By R. F. Scharff, 



B.Sc, Ph.D., F.Z.S. Pp. vii + 364 ; illustrated. 



(London : Walter Scott, Ltd., 1899.) 



''"T'HE title that we have chosen for this review of Dr. 

 J- ScharfT's volume is really rather more expressive 

 of the scope of the book than is his own title. For he 

 deals at greater length with the fauna of our own country 

 than with that of Europe in general. This is by no 

 means a defect to be urged in considering his statements 

 and arguments ; on the contrary, we think that it will 

 add to the interest of the book ; and besides Great 

 Britain has a fauna which practically only differs from 

 that of adjacent parts of Europe in its poverty. The 

 reduction of the number of individuals and of species of 

 indigenous creatures was set down by Mr. Wallace to 

 the recent glaciation of these islands, which, occurring, as 

 it was supposed to do, after the land connection with 

 Europe had been broken through, destroyed many forms 

 coming originally from more southern regions. The 

 severance of the land connections hindered a repopula- 

 cion when more favourable climatic conditions were re- 

 established. Dr. Scharff is one of those who do not believe 

 in great possibilities of migration over stretches of sea 

 for purely terrestrial animals. There are of course such 

 cases on record ; but they are really not numerous. Dr. 

 Scharff mentions several that are of recent occurrence. 

 Me tells us that Colonel Fielden, when in the Barbadoes, 

 witnessed, or heard of, the arrival of an alligator which 

 must have traversed a tract of ocean of 250 miles. There 

 are also well-known experiments which show that animals 

 '///■>/;/ be imported in a natural way from distant and 

 cranspontine countries. The resistance of certain snails 

 and other molluscs to the effects of sea-water when 

 guarded by their diaphragm has been proved by the 

 < lassical experiments of Darwin. It is, however, dis- 

 appointing to learn from Dr. Scharff how dangerous it is 

 to argue from experiments which can so readily be made 

 to the actual phenomena of nature. 



Concerning one of these protected and — as it was 

 thought— adventurous molluscs, the author writes as 

 follows : — 



"The fact that Cyclosioma clegans does not live in 

 Ireland is of particular interest in connection with the 

 floating-theory just quoted, as on all sides of Ireland 

 dead specimens have been picked up on the shore, show- 

 ing that marine currents carry specimens, and have thus 

 transported them for countless centuries. Nevertheless, 

 the species has not established itself in Ireland." 



Equally strong arguments can be derived from the 

 study of other islands, from which a species, that ought 

 to be there, as it were, is unaccountably absent. It has 

 always appeared to the present writer that in deducing 

 results from the faunas of oceanic islands which must 

 have been stocked de tioto from adjacent mainlands too 

 little weight has been given to involuntary introduction 

 by man. There is no doubt whatever that emigrating 

 man has been a most fell agent in the destruction of 

 faunas by the deliberate introduction of domestic and 

 other animals ; it is also probable that much has been 

 done in the way of accidental introduction. There is, 

 NO. I «0, VOL. 61] 



however, another possibility -urged by Dr. Scharff him- 

 self elsewhere in his volume— that may account for a 

 given species not succeeding in' establishing itself in a 

 country which appears to be ideal for its needs. There 

 may be no room for it ; the ground may be taken up by 

 an allied form or a creature of similar needs and habits. 

 Here again the problem is indefinitely complicated by 

 \ human occupation and tillage— in the case of the 

 j countries which form the subject of Dr. Scharff's re- 

 I marks. Another matter of wide zoo-geographical interest, 

 j as well as vital to the development of his argument, is 

 j dealt with by Dr. Scharff. The peopling of these islands 

 has, he thinks, mainly at least occurred along land routes ; 

 but how is it to be decided whence a given animal started 

 in its wanderings towards the British Islands.'' 



The author gives an example where a fair guess may 

 be made as to the original home of the genus. 



"The badger," he observes, "inhabits Europe and 

 Northern Asia. It is absent apparently from many 

 parts of Central Asia, but it appears again further south 

 in Palestine, Syria, Persia, Turkestan, and Thibet. West 

 Central Asia would be about the centre of its range. 

 That this corresponds to its place of origin is indicated 

 by the fact that the only three other species of badgers 

 known, viz., M. aftakuina, M. leucurus, and M. albo- 

 gulatis, are confined to Asia. If we examine the fossil 

 history of the genus, we find that the two most ancient 

 instances of the existence of badgers have been discovered 

 in Persia, where iVI. Polaki and M. maraghanus occur 

 in Miocene deposits." 



Failing future discoveries of fossil badgers, this method 

 of argument seems to be valid. But it is not so clear 

 to us that Dr. Scharff is justified in stating that the 

 centre of distribution, i.e. the original home of the genus, 

 is to be sought for where the number of species of the 

 genus is at a maximum. There are more species of the 

 Tapir ( Tapirus) in America than m Asia, where there is 

 only one. But it is doubtful as to whether the genus is 

 of American origin ; it is much more probably European. 

 So, too, with the cat tribe ; the species of Felis abound 

 in Asia and the East generally, and are fairly numerous 

 in America, but Europe again would seem to be the 

 place of dispersal. 



From these general considerations, which are put for- 

 ward with clearness and supported by a proper treat- 

 ment, so far as we can judge, of the geological evidence, 

 the author proceeds to discuss in detail the actual homes 

 of our British animals, laying most stress upon, or at 

 least dealing more at length with, the mammalia. Natur- 

 ally this is the most important group in attacking the 

 problem, since our acquaintance with fossil invertebrates, 

 and even of other vertebrates, is less extensive. The 

 fauna of this country, as everybody knows, is a mixture 

 of various and apparently incongruous elements. 



The facts brought forward by Dr. Scharff show inci- 

 dentally how very little influence temperature seems to 

 have, and to have had, in the limiting or encouraging 

 the migrations of mammalia. The tiger barred and the 

 leopard are at home in tropical forests and in the colder 

 regions of Asia. The polar bear, par excellence an Arctic 

 animal, endures with comfort the temperature of London 

 in the summer -and, indeed, more than endures it — as is 

 shown by the fact that an individual lived for thirty- 

 seven years in the Zoological Society's gardens. Dr. 



