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SCIENCE-GOSSIP. 



appearance is much what we should expect from 

 one whose whole development has been a struggle 

 against desperate odds. It is dwarfed in stature, 

 rarely exceeding twenty feet in height, and its 

 stunted trunk does not measure more than a foot 

 in diameter. Its rugged branches are twisted and 

 bent into grotesque shapes, which speak plainly of 

 a mute, sullen resistance. The leaves clothing the 

 branches are course, rough, and hard in texture. 

 The flowers grow in small spikes, insignificant and 

 without beauty ; they have no need to appeal to 

 the eye of either man or beast. Each flower 

 produces two seeds in a leathery pod-like case ; the 

 whole tree is built on a resistant plan. Each seed 

 is a flat oblong, and has attached to it a membranous 

 wing. The flowers develop after the rainy season, 

 and the seeds mature during the great drought. 

 When the fires rush over the plains the pods have 

 burst, and the hot currents of air catch up the 

 little winged seeds and carry them along, scattering 

 them far and wide, Thus the tree effects its aim — • 

 the dispersal of its seeds through the agency of the 

 flames, and the short exposure to the heat does not 

 injure their dry tough nature. The presence of 

 wings in seeds which rely on the wind as a carrier 

 is not at all uncommon ; the pine, for instance, 

 provides its seed with a comparatively large wing, 

 and pine-seeds are often carried great distances. 

 When the chaparro seeds germinate they are found 

 to have been scattered in wonderful order and 

 without crowding, a result probably due to some 

 regularity of the flame currents, and the planta- 

 tions that form are most noticeable for the 

 systematic arrangement of the trees ; in fact, they 

 have every appearance of having been planted and 

 kept by man's agency. This is a fact which 

 strikes particularly on the attention, for so often 

 where nature is left to herself, we have terrible 

 overcrowding and a most desperate battle for the 

 survival of the fittest. 



Why is this tree so remarkably adapted for the 

 fight with fire ? The secret lies in the peculiar 

 bark which covers it like a skin. Bark arises on 

 trees from the dried-up outermost tissues of the 

 stem being rejected and pushed off, as the stem, in 

 its natural course of growth, forms new tissue 

 from within. In no trees has the outer portion of 

 the bark any organic function ; when retained it 

 always serves a purely protective purpose. In the 

 chaparro this outer bark to the thickness of about 

 half an inch, is arranged in loose layers, and it has 

 become thickened and modified to such a degree 

 that the protection against ordinary dangers is 

 extended to the case of fire. In addition to being 

 practically fire-proof, its arrangement in the loose 

 layers renders it a non-conductor of heat, and 

 therefore the delicate inner tissues of the tree 

 remain unharmed during the scorching but brief 

 onslaught of the savanna fire. 



The home of the chaparro is emphatically these 

 fire-swept plains. In Colombia its plantations 

 cover vast areas ; they are found touching the sea- 

 coast on the north, and again a thousand miles 

 inland ; they may be on the level plain or high up 

 on the surrounding hills at an elevation of a 

 thousand feet or more. It is at a disadvantage, 

 however, in situations where other trees can live ; 

 it can defy the fire, but it succumbs in a struggle 

 for existence with others of its kind. All its energy 

 appears to have gone in the fight with its one 

 particular foe. 



The natives of Tolima, one of the United States 

 of Colombia, credit the chaparro with yet another 

 virtue. They assert that it will only grow where 

 there is gold in the soil below, and that, therefore, 

 it serves as a true guide to the seeker after riches. 

 This belief, however, rests at present only on 

 tradition, for though it undoubtedly grows in 

 auriferous regions, it has yet to be proved that it 

 grows in no others. 



This humble fire-proof tree is bestowing great 

 benefit on the land, and is slowly improving it. 

 The plantations are a protection against the fierce 

 rays of the sun, for under their shelter it is not 

 possible for the land to be so parched ; moreover, 

 they attract what little moisture there is in the air, 

 and so the chaparro plantations, during the dry 

 season, almost play the part of oases in the desert. 

 Mr. Thomson points out that the chaparro's work 

 in the amelioration of the land might easily be 

 accelerated and extended were man to step in and 

 assist nature by a " few simple devices." 



The chaparro is not the only tree which can 

 resist, to a very great extent, the action of fire, 

 though, probably, to no other is the fire so 

 congenial, and, therefore, it may be fairly claimed 

 as the " king of fire-proof trees." Certain euphor- 

 bia trees, close allies of the chaparro, have been 

 noticed in Africa to survive the grass-fires with 

 only a few scorches. It was surmised that here 

 too the secret of their immunity lay in their bark, 

 and specimens were submitted to Professor Farmer 

 for examination. His report confirmed this idea. 

 In it he states that all pieces submitted " agree in 

 possessing cells which show a certain amount of 

 gummy degeneration of the cells in the bark, 

 together with the presence of a considerable 

 amount of sclerotic cells " ; and his conclusion is 

 that " it seems not impossible that these two facts 

 may be connected with the resistance of the plants 

 to the fire." 



I, Charles Street, Leicester; May, 1896. 



M. A. Hermann, of 8, Rue de la Sorbonne, 

 Paris, has sent us his catalogue of botanical and 

 zoological books, comprising works in all languages, 

 which occupies seventy-eight pages, varying in 

 price from ninepence to fifty pounds. This will be 

 found useful to many of our readers, as titles 

 appear that are not often seen in English catalogues. 



