26 



NATUKAL HISTORY OF THE PEIMEVAL WOELD. 



all its glowing hues, we should stand silent with awe 

 and wonder ! Strange birds wandered over the sandy 

 shores or waded through the silt and mud of the estu- 

 aries; huge reptiles lurked among the herbage in quest 

 of prey; horrible vampire-like pterodactyles whirled 

 and veered from tree to tree; gigantic crocodiles basked 

 in the shallow waters; and huge tortoises loitered in 

 the recesses of lonely islands. Shark-like genera of 

 fishes swarmed in the seas, defending themselves with 

 their bristling fin-spines against the attacks of the ocean 

 monsters, or crushing tlieir crustacean victims between 

 their corrugated teeth. But of these we have already 

 spoken. What shall we say of the vegetation of the 

 period ? The continents, then slowly rising above the 

 waters, were enriched with a prodigality of verdure of 

 which the earth in our own days nowhere presents an 

 example or a counterpart. The atmospheric and cli- 

 matic conditions then prevailing were highly fiivour- 

 able to this luxuriance. The temperature was still of 

 great elevation ; the atmosphere humid, with frequent 

 rains and mists ; and when these passed away a glori- 

 ous sun shone in a cloudless burning sky. The Voltzias 

 of the Trias have disappeared, but the palms have 

 grown more numerous, and convert the forest glades 

 into still, shadowy avenues of graceful columns ; the 

 gigantic calamites likewise remain ; and though the 

 arborescent ferns have lost the enormous dimensions 

 of their predecessors in the Carboniferous period, they 

 preserve tlieir fine and delicately chiselled leaves. 



An entire family, the Cycads, now make their first 

 appearance, and develop themselves in three predo- 

 minant genera — the Zamitcs, the Pterophyllum, and 

 the Nilssonia. The trunk of the Zamites, simple, and 

 covered with the scar-like memorials of old foliage, 

 supports a thick crown of leaves, more than six feet in 

 length, which are disposed like plumes around a com- 

 mon centre. 



The Pterophylhnn is a tall, robust tree, clothed in 

 large pinnated leaves from top to bottom. Their thin 

 membranous leaves, trembling in the lightest breeze, 

 are provided with truncated leaflets, traversed by fine 

 nervures, not convergent, but all abutting on the ter- 

 minal truncated edge. 



The Nilssonia somewhat resembles the Pterophyl- 

 lum, but its leaves are thick and leathery in texture, 

 witli short leaflets contiguous, and, in part, attached 

 to the base ; at the summit they are truncated, or, more 

 correctly speaking, obtuse, with nervures arching or 

 confluent towards that summit. 



But let us picture to ourselves the Liassic world, not 

 with its forests of cycads and conifers, its masses of 

 ferns and equiseta, its rolling rivers, or its tepid 

 marshes; let us call up before our inner vision the 

 billows of the seething ocean, with a dull, cloudy heaven 

 bending over them, and the ichthyosaurus and the 

 plesiosaurus contending for their prey. The latter 

 arches its long neck to pounce suddenly on its mighty 

 antagonist, which spouts from its blow-holes, like our 

 modern whale, incessant jets of water, mucus, and 

 vapour (Plate 3). * 



We may next permit ourselves a glance at the flora of 



• Such is the opinion of liayle, but we Jo not tliinl; it is held 

 by the best living palteontologists. 



this period. As in the Triassio age, terrestrial vegeta- 

 tion mainly consisted of ferns, cycads, and conifers. 

 The first was represented by the Pachypteris micro- 

 phylla, the second by the Zamites Moreana; among 

 the conifers were conspicuous the Brachyphyllum 

 Moreaniira and Brachyphyllum majus. We find 

 palms, lilies, and similar monocotyledonous plants 

 largely on the increase ; and dicotyledonous types 

 exhibiting themselves in fragments of wood, leaves, 

 and inflorescence. This change in the character of 

 the terrestrial vegetation was necessitated by the 

 change which had taken place in the conditions of 

 our planet. The seas were more connected, and 

 showed a tendency to spread southward, while the 

 land assumed a more continental aspect, and the 

 channels of the great rivers and the boundaries of 

 inland lakes became more closely defined. 



Of the marine flora our knowledge is imperfect. 

 Aquatic plants, not unlike the pond-weeds of our own 

 days, seem to have flourished abundantly. Among the 

 cryptogams, equiseta (or mare's-tails) and lycopods (or 

 club-mosses) still preserved tlieir vitalit}'. Tree-ferns, 

 such as the Sphenopteris, TiEniopteris, and Peropteris, 

 accumulated in warm humid places ; while coni- 

 ferous trees began to predominate in the forests. So 

 nearly do these resemble, in many important respects, 

 the cypresses, araucarias, screw-pines, yews, and 

 thujas of New Zealand and other soutlicrn regions, 

 that they have received botanical names indicative of 

 these affinities — cupressites, araue.irites, pinites, fax- 

 ites, and thujites. Just such a landscape as a modern 

 naturalist shows us in the neighbourhood of Para (in 

 Brazil),* we may imagine to have been frequent enough 

 in the Jliddle Oolitic globe : — " We found ourselves," 

 he says, "in a moderately broad pathway, or alley, 

 where the branches of the trees crossed overhead and 

 produced a delightful shade. The W'oods were at first 

 of recent growth, dense, and utterly impenetrable ; the 

 ground, instead of being clothed with grass and shrubs 

 as in the woods of Europe, was everywhere carpeted 

 with Lycopodiums (club-mosses). Gradually the scene 

 became changed. We descended slightly from an 

 elevated, dry, and sandy area to a low and swampy one; 

 a cool air breathed on our faces, and a mouldy smell 

 of rotting vegetation greeted us. The trees were now 

 taller, the underwood less dense, and we could obtain 

 glimpses into the wilderness on all sides. The leafy 

 crowns of the trees, scarcely two of which could be 

 seen together of the same kind, were now far away 

 above us, in another world, as it were. Wo could only 

 see at times, where there was a break above, the tracery 

 of the foliage against the clear blue sky. Sometimes 

 the leaves were palmate, or of the shape of large out- 

 stretched hands ; at others, finely cut or feathery, like 

 the leaves of MimosK. Below, the tree trunks were 

 everywhere linked together by sipos ; the woody, flexi- 

 ble stems of climbing and creeping trees, whose foliage 

 is far away above, mingled with that of the smaller 

 independent trees. Some were twisted in strands, 

 like caller; others had thick stems contorted in every 

 variety of shape, entwining snake-like round the tree 

 trunks, or forming gigantic loops and coils among the 

 * Bates, The Natm-alist on the Amazons. 



