LEAVES FROM THE NOTE-BOOK OF A NATURALIST. 



109 



eight pounds, and were reduced and worn so smooth 

 from their original angular roughness, that they 

 seemed to have remained there many months. 



Dr. Buckland, in his Bridgewaler Treatise, well 

 observes, that in the living subgenera of the croc- 

 odilian family we see the elongated and slender 

 beak of the gavial constructed for feeding on fishes ; 

 whilst the shorter and stronger snout of the broad- 

 nosed crocodiles and alligators gives them the 

 power of seizing and devouring quadrupeds that 

 come to the banks of rivers in hot countries to 

 drink. As there were scarcely any mammalia 

 during the secondary periods, while the waters 

 were abundant, we might, a priori, expect, he 

 remarks, that if any crocodilian forms then existed, 

 they would most nearly resemble the modern gavial. 

 Accordingly, those genera only which have elon- 

 gated beaks have been found in formations anterior 

 to, and including the chalk ; whilst the true 

 crocodiles, with a short and broad snout like the 

 alligator, appear for the first time in strata of the 

 tertiary periods in which the remains of mammalia 

 abound. 



Though neither crocodile nor alligator exists in 

 Europe, nor ever, I believe, has existed there since 

 that quarter of the globe was peopled, there was a 

 time when this now temperate island must have 

 teemed with animals only able to exist in warm 

 latitudes, and when its hotter clime presented a 

 congregation of all the crocodilian forms now so 

 widely scattered and separated. What geograph- 

 ical changes has the world undergone since that 

 time ! How different was the face of this fair 

 island before the eocene deposits were formed ! 



At the present day the conditions of earth, air, 

 water, and warmth, which are indispensable to the 

 existence and propagation of these most gigantic of 

 living saurians, concur only in the tropical or 

 warmer temperate latitudes of the globe. Croco- 

 diles, gavials, and alligators, now require, in order 

 to put forth in full vigor the powers of their cold- 

 blooded constitution, the stimulus of a large amount 

 of solar heat, with ample verge of watery space for 

 the evolutions which they practise in the capture 

 and disposal of their prey. Marshes with lakes 

 extensive estuaries large rivers, such as the Gam- 

 bia and Niger, that traverse the pestilential tracts 

 of Africa or those that inundate the country 

 through which they run, either periodically, as 

 the Nile for example, or with less regularity, like 

 the Ganges ; or which bear a broader current of 



tepid water along boundless forests and savannas, 

 like those ploughed in ever-varying channels by the 

 force of the mighty Amazon or Oronooko such 

 form the theatres of the destructive existence of the 

 carnivorous and predacious crocodilian reptiles.* 



Well may the gifted professor ask, What must 

 have been the extent and configuration of the 

 eocene continent which was drained by the rivers 

 that deposited the masses of clay and sand, accu- 

 mulated in some parts of the London and Hamp- 

 shire basins to the height of one thousand feet, and 

 forming the graveyard of countless crocodiles and 

 gavials 1 whither trended that great stream, once 

 the haunt of alligators, .the resort of tapir-like 

 quadrupeds, the sandy bed of which is now exposed 

 on the up-heaved face of Hordwell Cliff? 



No one is better qualified to give an answer to 

 such questions than the deep-thinking and eloquent 

 querist. Everything must fade after the vivid 

 picture here presented, and with it we close the 

 scene : 



Had any of the human kind existed and traversed 

 the land where now the base of Britain rises from 

 the ocean, he might have witnessed the gavial 

 cleaving the waters of its native river with the ve- 

 locity of an arrow, and ever and anon rearing its 

 slender snout above the waves, and making the banks 

 reecho with the loud and sharp snappings of its 

 formidably-armed jaws ; he might have watched 

 the deadly struggle between the crocodile and pa- 

 leeothere, and have been himself warned by the 

 hoarse and deep bellowings of the alligator from 

 the dangerous vicinity of its retreat. Our fossil 

 evidences supply us with ample materials for this 

 most strange picture of the animal life of ancient 

 Britain, and what adds to the singularity and inter- 

 est of the restored tableau vivant is the fact, that it 

 could not now be produced in any part of the world. 

 The same forms of crocodilian reptiles, it is true, 

 still exist, but the habitats of the gavial and the 

 alligator are wide asunder, thousands of miles of 

 land and ocean intervening ; one is peculiar to the 

 tropical rivers of continental Asia, the other is re- 

 stricted to the warmer latitudes of North and South 

 America ; both forms are excluded from Africa, in 

 the rivers of which continent true crocodiles alone 

 are found. Not one representative of the crocodil- 

 ian order naturally exists in any part of Europe ; 

 yet every form of the order once flourished in close 

 proximity to each other in a territory which now 

 forms part of England .f 



* Owen's History of British Fossil Reptile*. 

 t Ibid. 



PART XIII. 



Mettez les deux chameleons ensemble 

 Celuy d'Egypte, et celui d'Arabie ; 

 On trouvera difference en leur vie, 

 Mesme en couleur 1'un 1'autre ne ressemble, 



Says the quatrain with which the portrait of the 

 chameleon* is enriched in the Portraits d? Oyseaux, 

 Animaux, Serpens, Herbes, Arbres, Hommes el 

 Femmes, observez par P. Belon du Mans, and the 

 record is true. Of this curious form of the lacer- 



* The ancients wrote of an herb of the same name 

 which grew among the rocks on the sea-shore, and 

 changed the color of its flowers thrice a day. 



8 



tine race there are several species, and every year 

 many arrive in this country to linger out an 

 unnatural existence of a few weeks. 



In a state of freedom, and in its natural haunts, 

 the chameleon would seem to be a very different 

 being from the torpid invalid seen here in confine- 

 ment. Hasselquist speaks almost rapturously of 

 it, calling it an " elegant creature." He tells us 

 that it is frequently found in the neighborhood of 

 Smyrna, particularly near the village Sedizeud. 

 There he describes it as climbing the trees, and 

 running among the stones. The people of the 



