August 51, 1882] 



NATURE 



435 



Definition 0/ Tertiary Period by Placental Land Mammals. 



Historic ; in 

 wbichthe events 

 are recorded in 

 history. 



Prehistoric ; in 

 which domestic 

 animals and 

 cultivated fruits 

 appear. 



Events included in 

 history. 



Man abundant ; do- 

 mestic animals, 

 cultivated fruits, 

 spuming, weaving, 



pottery - making, 

 uaining, commerce; 

 the neol thic, 



bronze, and iron 

 stages of culture. 

 Man appears ; An- 

 thropida ; the 

 palaeolithic hunt- 

 er ; living species 

 abundant. 



Founded on discove- 

 ries, document-, 

 refuse - heaps, 

 caves, tombs. 



Camps, habitations, 

 tombs, refuse- 

 heaps, surface ac- 

 cumulation, caves, 

 alluvia, peat-bogs, 

 submarine forests, 

 raised beaches. 



Pleistocene ; in Man appears ; An- ' Refuse-heaps, con- 

 which living thropids ; the I tents of caves, 

 species of pla- palaeolithic hunt- riverdeposiis, sub- 

 cental mammals er ; living species marine forests, 

 are more abun- abundant. boulder - clay, 

 dant than the ' moraines, marine 

 extinct. sands, and shingle. 



Ill Pleiocene ; in Living species ap- Fresh - water and 



which living pear ; apes, Sim:- marine strata ; 



s] ecies of pla- ada, in Southern volcanic debris 



cental mammals Europe. (Auvergne). 

 appear. 



II. Meiocene ; in ! Living genera ap- Fresh - water and 

 which the al- ; pear ; apes, Stmt- ' marine strata ; 

 a ! <r, inEuropeand volcanic debris 

 North America. (Auvergne) ; lig- 



nites. 



liance between 

 living and pla- 

 cental mammals 

 1 i m >re close 

 than before. 



Eocene ; in 

 which the pla- 

 cental mammals 

 now on earth 

 were repre- 

 sented by allied 

 forms belong- 

 ing to existing 

 oraers and 



families. 



Living orders and Fresh - water and 

 families appear; marine strata; 



\enmry(Lemurid,r) lignites, 

 in Europe and 

 North America. 



The orders, families, genera, aid species in the above table, 

 when traced forward in time, fall into the shape of a genealogical 

 tree, with its trunk hidden in the Secondary period, and its 

 branchlets (the living species) passing upwards from the 

 Pleiocene, a tree of life, with living Mammalia for its fruit 

 and Foliage, Were the extinct species taken into account, it 

 would be seen that they fill up the intervals separating one 

 living form from another, and that they too grow more and more 

 like the living forms as they approach nearer to the present day. 

 It must be remembered that in the above definitions the fossil 

 marsupials are purposely ignored, because they began their 

 specialisation in the Secondary period, and bad arrived in the 

 Eocene at the stage which is marked by the presence of a living 

 genus — the opossum (Didelphys). 



It will be seen, from the examination of the above table, that 

 our inquiry into the antiquity of man is limited to the la-t four 

 of ihe divisions. The most specialised of all animals cannot be 

 looked for until the higher Mammalia by which he is now sur- 

 rounded were alive. We cannot imagine him in the Eocene age, 

 at a time when animal life was not sufficiently differentiated to 

 pre-ent us with any living genera of placental mammals. Nor 

 is there any probab lity of his having appeared on the earth 

 in the Meiocene, because of the absence of higher placental 

 mammals belonging to. living species. It is most unlikely that 

 man shou'd have belonged to a fauna in which no other living 

 species of mammal was present. He bel irigs to a more ad- 

 vanced stage of ev lurion than the mid-Meiocene of Thenar, 

 as may be seen by a reference to the preceding table. Up to 

 this time the evolution of the animal kingdom had advanced no 

 farther than the Sim adx in the direction of man, and the apes 



then haunting the forests of Italy, France, and Germany, repre- 

 sent the highest type of those on earth. 



We may also look at the que-tion from another point of view. 

 If man were upon the earth in the Meiocene age, it is in- 

 credible that he should not have become something else in the 

 long lapse of ages, and during the changes in the conditions of 

 life by which all the Meiocene land Mammalia have been so 

 profoundly affected, that they have been either exterminated, or 

 have assumed new forms. It is impossible to believe that man 

 should have been an exception to the law of change, to which 

 all the higher Mammalia have been subjected since the Meiocene 

 age. 



Nor in the succeeding Pleiocene age can we expect to find man 

 upon the earth, because of the very few living species of pla- 

 cental mammals then alive. The evidence brought forward by 

 Professor Capellini, in favour of Pleiocene man in Italy, seems 

 both to me and to Dr. Evans unsatisfactory, and that advanced 

 by Professor Whitney in support of the existence of Pleiocene 

 man in North America, cannot in my opinion be maintained. It 

 is not until we arrive at the succeeding stage, or the Pleistocene, 

 when living species of Mammalia begin to abound, that we 

 meet « ilh undisputable traces of the presence of man on the 

 earth. 



The Pleistocene Period. — As a preliminary to our inquiry we 

 must first of all define what is meant by the Pleistocene Period. 

 It is the equivalent of the Quaternary of the French, and the 

 Posrpleiocene of the older works of Lyell, and it includes all the 

 phenomena known in latitudes outride the Arctic Circle, where 

 ice no longer is to be found, under the name of glacial and inter- 

 glacial It is characterised in Europe, as I have pointed out in 

 my work on "Early Man in Britain," by the arrival of living 

 species, which may be conveniently divided into five groups, 

 according to their present habi'ats. The first consists of those 

 now found in the temperate zones of Europe, Asia, an 1 North 

 America. It includes the following animals : — 



Mole, musk shrew, common shrew, mouse, beaver, hare, pika, 

 pouched marmot, water-vole, red field-vole, short-tailed field- 

 vole, Continental field-vole, lynx, wild cat, wolf, fox, marten, 

 ermine, stoat, otter, brown bear, grisly bear, badger, horse, 

 bison, v .:;, saiga antelope, stag, roe, fallow-deer, wild 



The second consists of animals of arctic habit : — 



Russian vole, Norwegian lemming, arctic lemming, varying 

 hare, musk sheep, reindeer, arctic fox, glutton. 



The third is composed of those which enjoy the cold climate 

 of mountains : — 



The snowy vole, Alpine marmot, chamois, and ibex. 



The-e animals invaded Europe from Asia, and as the cold 

 increased, the temperate group found their way into Southern 

 Europe and Northern Africa, while the arctic division pushed 

 as far s-uith as the Alps and Pyrenees. 



The fourth group of invading forms is represented by animals 

 now only found in warm countries : — 



Porcupine, lion, panther, African lynx, Caflre cat, spotted 

 hyena, striped hyena, and African elephant. 



This group of animals is found as far to the north as Yorkshire, 

 and as far to the west as Ireland. Among the southern animals, . 

 too, must be reckoned the hippopotamus, which lived as far 

 north as Britain in the Pleiocene age, and in the Pleistocene occurs 

 in caves and river deposits, in intimate association with some 

 arctic species, such as the rein eer. 



The fifth group is composed of extinct species, hitherto unknown 

 in Europe in the Pleistocene age, such as — 



The straight-tusked elephant, mammoth, the pigmy elephants, 

 woolly and small-nose rhinoceroses, the Irish elk, pigmy hippo- 

 potamus, and the cave bear. 



The question as to which of these groups the River-drift liaian 

 belongs must be deferred till we can take a survey of the evidence 

 elsewhere. 



The early Pleistocene division is characterised by the presence 

 of the temperate and southern species in Britain ; the middle 

 stage by the presence of the arctic, hut not in full force ; and the 

 late Pleistocene by the abundance of arctic animals, not only in 

 Britain, but on the Continent as far as the Alps and Pyrenees, 

 and the lower valley of the Danube. 



The Early Pleistocene Forest and Mammals of East Anglia. — 

 The first view which we get of the Pleistacene Mammalia in this 

 country is offered by the accumulations associated with the buried 

 forest of East Anglia. It extends for more than forty miles along 

 the -h ires of Norfolk and Suff .Ik, from Cromer to Kessingland, 

 passing in'o the cliff on the one band and beneath the sea on the 



