NATURAL HISTORY OF THE PRIMEVAL WORLD. 



resistance of the part seized, and bringing it down to the 

 body. 



For the long and slender branchial and anti-branchial 

 bones of the climbing sloth we find substituted in its 

 gigantic predecessor a humerus, radius, and ulna of 

 more robust proportions ; of such proportions, indeed, 

 in the Mylodon robustus, as are unequalled in any other 

 known existing or extinct animal. 



The tree being thus partly undermined and firmly 

 grappled with, the muscles of the trunk, the pelvis, and 

 the hind limbs, animated by the nervous influence of 

 the unusually large spinal chord, would combine their 

 forces with those of the anterior members in the efforts 

 at prostration. 



"And now," says Professor Owen, "let us picture 

 to ourselves the massive frame of the Megatherium, 

 convulsed with the mighty wrestling, every vibrating 

 fibre reacting upon its bony attachment with a force 

 which the sharp and strong crests and apophyses loudly 

 bespeak. Extraordinary must have been the strength 

 and proportions of that tree, which, rocked to and fro, 

 to right and left, in such an embrace, could long with- 

 stand the incessantly repeated efforts of its ponderous 



A complete skeleton of the Mylodon was discovered 

 at Buenos Ayres. It measured eleven feet from the 

 fore-part of the skull to the end of the tail. It probably 

 belonged to a young individual. 



Our survey of the animal life of the Pleistocene 

 period next brings us to the Glyptodon, another of the 

 South American quadrupeds, covered, like the modern 

 armadilloes, with a stout, tesselated, bony armour. In 

 size it equalled the largest rhinoceros. It was, in fact, 

 a colossal or magnified armadillo, which it resembled 

 in its habits, food, and principal structural peculiarities. 

 "Otherwise its armour," as a writer has pithily observed, 

 '' would cover more than a score of armadilloes." 



It is obvious, however, putting aside the question of 

 bulk, that the marked peculiarity of the Pleistocene 

 period is the approximation of its forms of animal life 

 to those of the present age. The megathere is the 

 natural forerunner of the sloth ; the glyptodon of the 

 armadillo ; the mammoth of the existing elephant ; the 

 macrauchenia of the modem llama; and the mery- 

 cothere of the camel. 



In the Eocene stage of the Quaternary epoch we find 

 the fauna of Europe characterized by its palseotheres, 

 anoplotheres, xiphodons, river-hogs, alligators, croco- 

 diles, gavials, and turtles ; in the Pleiocene sub-period 

 these decline, or become extinct, and their places are 

 occupied by mastodons, mammoths, deinotheres, camels, 

 giraffes, cave-bears, lions, and hyaenas. We come still 

 pearer to what we may call the modern world, and in 

 the Miocene period distinguish, as the principal forms 

 of quadrupedal life, mammoths, hippopotami, rhino- 

 ceroses, antelopes, wild oxen, tigers, bears, and horses. 

 A similar gradation is noticeable in Asia, where the 

 middle sub-period was characterized by numerous spe- 

 cies of si vatheres, elephants, camels, lions, tigers, giraffes, 

 crocodiles, and huge tortoises ; the upper period, by the 

 horse, ass, urus, rhinoceros, and mammoth. The 

 forms of North America are so like those of Europe as to 

 suggest the existence of a closer communication between 



the two continents in those days than now obtains. 

 In South America we ascend by a succession of similar 

 stages to the megathere, the scelidothere, the megal- 

 onyx, the mylodon, the glyptodon, and the macrauchene. 

 The remarkable Marsupials of Australia were similarly 

 anticipated by the gigantic Diprotodon ; the wingless 

 birds of New Zealand by the Palsepteryx and the 

 Dinornis ; and the African ostrich by the huge Epiornis 

 of Madagascar. 



We shall close our sketches of the natural history 

 of the primeval world with a glance at the last-named 

 forms of animal life the wingless birds. 



The Dinornis* is a genus of large birds of the tribe 

 Brevipennes. No species of it is now known to exist. 



Uinorni;, aud 



but its bones have been discovered in the upper Pk-io- 

 cene deposits in New Zealand in caves, in marshes, 

 in beds of rivers, and on the sandy shore. From 

 certain traditions still current among the natives this 

 bird would seem to have survived, along with its con- 

 geners the PalsQpteryx and Aptornis, to the close of the 

 seventeenth or beginning of the eighteenth century. 

 Its New Zealand name is Moa. It is said to have 

 baen hunted for the sake of its flesh and the beautiful 

 feathers of its plumage. It was a stupid, lethargic 

 bird, incapable of flight, and living upon vegetable food 

 in the sequestered depths of the forests, or on the 

 topmost crags of the mountains. In size it greatly 

 exceeded any living bird, some of its bones being 

 double the dimensions of those of the ostrich, while 

 the body was even disproportionately bulkier. The 

 legs were long, and the Dinornis probably stood 

 * From ouicf. terrible ; ?nd r /nit , a bird. 



