3IO 



NATURE 



Feb. 3, 1 88 1 



in Europe "after the last great extension of glaciers" — 

 or in the Post-glacial times. 



There is also reason to believe that man was living 

 in Europe before and during the Glacial period, or, 

 in other words, in Pre-glacial, Glacial, and Inter-glacial 

 times, although the alleged discovery of man in the Vic- 

 toria Cave, relied upon by Dr. J Geikie, has been shown 

 to have been founded on a mistake, and the inter- 

 glacial age of the implements at Brandon and Thetford, 

 vi'hich he quotes as being of great importance, is not 

 accepted by very good judges such as Dr. Evans and 

 Prof. Hughes. These how"ever may be dismissed as 

 throwing no light on the question as to the existence of 

 man in Britain after the great extension of the glaciers. 



Dr. J. Geikie's method of arriving at the climate of his 

 "' Inter-glacial periods " is equally faulty. He considers 

 that they were warm and genial, because of the presence 

 of certain land shells, such as Cyrena fltiminalis, the 

 climatic value of which is at present unknown, of certain 

 marine shells, the distribution of which is dependent on 

 the warm and cold currents, and of land-mammalia now 

 found only in southern latitudes, such as the hippo- 

 potamus, the limit of w^hose endurance of cold is yet to 

 be proved, since those in the Zoological Gardens in 

 London will take their tubs in frosty weather. But, unfor- 

 tunately for his argument, the last animal is associated 

 with arctic species, such as the reindeer, in all the caves 

 (Kirkdale, Durdham Down, &c.) except two, and in all 

 the river deposits (Bedford, Acton, &c.) except some three 

 or four, in which it has been found in this country. With 

 equal reason we might argue that the climate was arctic 

 from the presence of reindeer. The consideration which 

 he urges, that the two groups of animals could not live 

 side by side because they do not live now, is met by the 

 direct testimony of their associated rema.ins, not merely 

 in this country but on the continent. The hysenas, for 

 example, of Kirkdale and of the Vale of Clwyd ate rein- 

 deer and hippopotamuses, and dragged them into their 

 dens, where their gnawed fragments occurred in one and 

 the same stratum. We may remark that in dealing witii 

 the fauna of the Victoria Cave Dr. J. Geikie omits all 

 notice of the reindeer, the presence of which destroys his 

 argument as to climate. This selection may be taken as a 

 fair sample of the mode in which he has dealt with the 

 whole evidence offered by the Pleistocene mammalia. 

 He deals with it, not with the impartiality of a judge, but 

 as an advocate ; and has only called those witnesses 

 which count on his side. The vast numbers of reindeer 

 associated with the remains of Palaeolithic man from the 

 caves of Cresswell as far as the Alps, and from the 

 Pyrenees into the valley of the Danube, prove that 

 the climate in those regions was in those times not 

 " a warm inter-glacial " climate, but one in harmony with 

 hat indicated by the blocks of stone in the gravels 

 pointed out by Prof. Prestwich. 



The interglacial net is spread far and wide over the 

 Continent. It includes not merely the forest with fig-trees 

 and Judas-trees and laurestinas of Moret, which, as 

 Saporta points out, would have been killed off by a spell 

 of hard frosts, to say nothing of such a climate as is 

 implied by the supposed preceding Glacial period, of 

 which there is no evidence in that locality. It covers the 

 deposits of Mont Perrier, near Issoire, from which MM. 



Croizet and Jobert obtained a rich fauna, universally con- 

 sidered typical upper Pleiocene. It covers also the 

 mammaliferous deposit of Liffe, near Gandino in the 

 Italian Alps, in which the mammalia identified by Forsyth 

 Major are unmistakably Pleiocene. It is even stretched 

 so as to take in the so-called Pleiocene man of Olmo, near 

 Arezzo, the age of which, as Dr. Evans has pointed out, 

 is proved to be Neolithic by the associated implements. 

 Thus we have things of widely different and of well-ascer- 

 tained age grouped together under the head of " inter- 

 glacial," and we have in this fact proof that the classifica- 

 tion is so far worthless, as indeed every system must be 

 which is based on ice, and ice only. 



In further illustration of this we may quote the view of 

 our author, that in the period usually termed Prehistoric, 

 or recent, but by him " Post-glacial," Europe was con- 

 nected by land with the Faroes, Iceland, and Greenland, 

 and that the climate was genial. It is assumed that 

 the "last glacial period" killed off all the Pleistocene 

 forests in those latitudes, and that the present traces 

 of forests are the residt of subsequent growths, extending 

 from one point to all the rest along a continuous tract of 

 land. If we allow this, surely in the far north, to say the 

 least, they are " interglacial," seeing that they are wedged 

 in between "the last Glacial period" and the present 

 glacial conditions. But we can allow neither his assump- 

 tion nor can we accept his geography. The Post-glacial 

 glaciers of Scotland spoken of on p. 526 seem to us proof 

 that the ice-classification breaks down, and the admission 

 that the Great Ice age is merely " a stage or phase of the 

 Pleistocene period " is a frank confession tending in that 

 direction. 



It is only necessary to say a few words about the two 

 large volumes of the Marquis de Nadaillac. His attitude 

 of reserve with regard to Meiocene and Pleiocene man is 

 judicial and impartial. But we would point out that here 

 and there in the work serious errors are to be remarked. 

 He considers, for example, the Archaeopteryx a tertiary 

 bird ; he associates the Liassic fish of Lyme Regis with 

 the "Tertiary fishes of Lebanon and Monte Bolca," and 

 he writes of the Ichthyosaurus and Plesiosaurus as if they 

 belonged to the Eocene age. 



In neither of these works can we find any addition to 

 what has been already known about Prehistoric Europe, 

 and in both there are omissions of well-known facts 

 which it is impossible to notice within the limits of these 

 columns. W. Boyd Dawkins 



THE BIOLOGY OF PLANTS 



Beitrdge zur Biologic der Pfianzen. Herausgegeben von 

 Dr. Ferdinand Cohn. Vol. ii. part 3, with 5 plates ; 

 vol. iii. parts i and 2, with 15 plates. (Breslau : J. U. 

 Kern, 1877, 1879, and 1880.) 



IN the concluding part of the second volume of the 

 well-known Bcitrdoc three out of four papers are 

 devoted to fungi and Bacteria, one only being physio- 

 logical. This physiological paper is by Dr. Just, on the 

 action of high temperatures upon the preservation and 

 germination of seeds. The experiments, which are 

 described in minute detail, were made with Nobbe's 

 germinating apparatus and a thermostat. Horstmann's 

 thermostat, which was the one employed for all tempera- 



