HAIIDWICKE'S SCIENCE-GOSSIP. 



147 



further south, either in the Old World or the New. 

 The reason why the southern states of North 

 America are now occupied by a flora which I have 

 shown you was decidedly European during the 

 Miocene period, is that it subsequently migrated 

 thither by way of that continuous land, whose 

 outliers are to be fouud in the Aleutian islands. 

 They were driven to their present southerly habitats 

 by the gradual growth of the great Arctic ice-cap 

 during the Pliocene epoch, and which, in extending 

 so far beyond its present limits during the Glacial 

 period, caused temperate plants to take up positions 

 even under the equator; but at sufficient heights 

 to find a temperature ' analogous to that of their 

 northern home. The further you go east in the 

 old world, the more numerous relatively are the 

 living species which occur in the fossil in the Swiss 

 lignites. The Salisburia is now limited to the 

 Japanese region, although it is found fossil in the 

 Pliocene deposits of North America. There are 

 more than three hundred existing species of plants 

 common to the Southern United States and Japan, 

 than to Europe. So that, in this respect, Japan is 

 more nearly related to the new world than to the 

 old. 



I have gone into this detail because, although the 

 vegetable forms which enter into my composition 

 are so like those now in existence, as to suggest 

 a recent geological period, yet their cosmopolitan 

 distribution from European centres, the subsequent 

 depression of dry land to become sea-beds, and the 

 uplifting of sea-bottoms into dry land, and even to 

 high mountains, all proclaim the great lapse of 

 time which must have ebbed away since then ! 

 Many of the great fresh-water lakes I spoke of 

 just now, set in their frame-work of a southern 

 vegetation, had rivers and streams which supplied 

 them with water. The deltas of such streams are 

 still visible in many parts of Central France. The 

 boughs of the overhanging trees, and the host of 

 leaves which were shed in the autumn time, thickly 

 strewed the surface : gradually settling to the 

 bottom, they there formed those beds of woody 

 lignite of which I form an insignificant part. In 

 some of the Swiss lakes there were precipitations 

 of limy matter going on, and these enveloped the 

 leaves, &c, with thin films of carbonate of lime, 

 so as to preserve every vein, mid-rib, and orna- 

 mental marking. The fish, such as the Roach, &c, 

 as well as fresh-water mussels, which lived in the 

 lakes, have their remains occasionally found in 

 numbers. In Central Erance there are beds of 

 some feet in thickness actually made up of the 

 accumulated tubes of caddis-worms ! More than a 

 thousand different species of insects have been ob- 

 tained from the lignite beds of Switzerland, so that 

 you may guess at the lively sounds which animated 

 these old Miocene woods. Gorgeous butterflies, 

 allied to existing Indian forms, slowly flapped their 



way through the bosky thickets. Hosts of white 

 ants, or Termites, of at least ten species, built their 

 earthy mounds ; myriads of insects, of various 

 orders, dropped into these extinct Swiss lakes by 

 millions, poisoned by the mephitic gases which were 

 sometimes evolved in great volume. Among the 

 fossil insects you may recognize forms which man- 

 kind now consider pests, although they have an 

 antiquity so much greater than themselves. These 

 include the Dung-beetles, Lady-birds, Earwigs, 

 Glow-worms, Dragon flies, Honey-bees, &c. 



I must say a few words respecting the creatures 

 which lived in these magnificent primeval forests. 

 Troops of monkeys were not wanting, of which the 

 remains of at least three different genera are known. 

 The Dnjopithecus, or " Tree-ape," lived in Erance. 

 It was arboreal in its habits, and in stature was 

 equal to a man. In Greece there lived a genus 

 called Semnopithecus, and in the forests where the 

 Pyrenees now rise was another, named Pliopithecus. 

 Huge tigers {Macluiirodus) haunted the thickets, 

 scaring the light antelopes and deer. Along with 

 the tree-monkeys were species of Opossum, not 

 much unlike those now living on the same trees in 

 the United States. Huge Deinotheria frequented 

 the marshy swamps — creatures with downward-bent 

 tusks, and, in natural history position, intermediate 

 between the Tapir and Elephant families. The 

 Mastodon was the characteristic and commonest 

 type of the elephants, noticeable chiefly for its 

 straighter tusks, and more particularly for the 

 maminillated shape of its huge teeth, which, how- 

 ever, were only employed on vegetable diet. The 

 rivers swarmed with many species of river or wart 

 hogs, associated with Hippopotami, Tapirs, &c. 

 Herds of wild oxen roamed over the plains, their 

 weaklier members falling a prey to the huge tigers, 

 bears, and hycenas, which had appeared on the stage 

 of creation by this time. The Deer family had also 

 come into existence, and abounded in great num- 

 bers. What was said of the mammalia of the 

 Eocene period, — viz., that some of the species com- 

 bined characters which are now distributed among 

 three or four, is more or less true of many of the 

 Miocene animals. I have mentioned the Deinotheria- 

 as instances. The Hipparion, or three-toed horse — 

 very numerous at this time, — was another, inasmuch 

 as it possessed affinities with the ruminantia. In 

 the Miocene deposits of the Sewalik Hills, in 

 India, the " missing links " are even more numerous : 

 chief among the forms there to be met with is the 

 Sivatherium, a huge four-horned deer, which con- 

 nected the ruminant family with the pachyderms. 

 It had a long snout, or proboscis, like the elephant, 

 which creature it nearly equalled in size and bulk. 

 But the most remarkable animal which then lived 

 in India was a huge Tortoise, now extinct, whose 

 entire length was over eighteen feet, breadth eight 

 feet, and height over seven feet ! I doubt whether 



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