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ultimately remained in possession of the plot. The plots under observation were 2 metres 30 cents. long, 1 metre broad, and all as nearly as possible under the same conditions, save that the soil was varied, in some cases consisting of the ordinary soil of the garden, in others of an admixture of lime, in others of sand, or of sand and lime, and so forth.
Of the 107 species under observation, all, or nearly all, found the most essential requisites of their existence equally well in all the varieties of soil; so that, other conditions being equal, the nature of the soil was indifferent. The species which remained victors, all the others being ultimately dispossessed, were Triticum repens (couch), Poa pratensis, Potentilla reptans, Acer Pseudo Platanus (sycamore), Camus sanguinea, native plants ; and Aster sal'ignus, A. par'utflorus, Euphorbia virgata, and Prunus Padus, derived from other portions of the garden.
It may, therefore, be inferred that the district in which these experiments were made would in process of time, if no obstacle were afforded, become covered with meadows and woods—meadows in the low ground and woods in elevated places. Again, the experiments show that the survival of certain plants has not been influenced by the nature of the soil; thus the couch-grass was ultimately spread over all the plots, whether of sand, or of loam, or of lime, whether drained or undrained. So also with Poa pratensis and Potentilla reptans. So that the chemical and physical nature of the soil, as has been so often shown in similar investigations, plays only a secondary part.
As-to the action of shade, it was found by Professor Hoffman that low-growing plants, especially if annuals, disappeared rapidly, while taller-growing plants, such as couch, Pmnus Padus, &c.. survived. The survival of certain plants, then— couch, Aster, Potentilla, &c.——is due much less to external conditions than to the “ habit” of the plant itself; that is to say, to the facility the plant has of adapting itself to varying external conditions, and thus of triumphing over others less favourably endowed in this wise.
The immediate source of victory lies in the powerful rootgrowth of the survivors, including under the general term “ root” not only the root proper, but the offshoots and runners which are given off just below, or on the surface of the ground. Indeed, the latter habit of growth is more advantageous to plants in such a struggle than the development of the true root downwards would be. Among those plants where the roots were equally developed there were, nevertheless, inequalities of growth, dependent probably on the greater need for light in some species than in others, &c.
It is clear from Professor Hoffman’s experiments that, but for the continual use of the hoe, and the diligent extirpation of the weeds in our fields, the stronger growing ones would not only destroy our crops, but also other weeds less vigorous than themselves. But they are not sufficient to explain all the conditions of this complicated problem; as is shown by the fact that in the district adjoining the locality where Professor Hoffman’s experiments were carried on, the predominant plants are not the same as those which ultimately proved victors in the experimental beds.
We may add, that for two years a series of observations was carried on in the gardens of the Royal Horticultural Society, at Chiswick, with a view to ascertain how certain selected plants, twelve in number, and naturally growing in pastures, would be affected when growing by themselves, by the addition of manures of five different descriptions, and similar to those used at Rothamsted. In some cases the results of these experiments were unsatisfactory, from circumstances that need not be detailed here; still a large body of facts was accumulated, and, with reference to the property by which certain plants prove victorious in the struggle for life, it was clear that the natural habit or organisation of the plant was, cwteris paribus, the mainspring of its success over its competitors. The several manures intensified or deteriorated this peculiar organisation, as the case might be, and thus favoured or impeded its growth accordingly.
0 animals are so abhorrent to most persons as are snakes. Their lurking habits and insidious approach, their anomalous aspect, their movements effected without the aid of limbs, above all their venom, usually excite feelings of disgust and apprehension. Yet 'the study of snakes attracts us, as snakes themselves are said to fascinate their victims. The biblical stories of the serpent beguiling Eve and of St. Paul’s miraculous escape from a poisonous snake at Melita, the famous myth of the sea-serpent, the worship of snakes in the East, the tricks of the snake-charmers—these, with other such-like traditions and customs, tend further to enhance its interest. Of animals directly formidable to man, none, beyond the limits of his own species, are so deadly as the poisonous snakes. Against their silent and sudden attack he guards himself with difliculty. Against their wounds he can seldom find a remedy.
Serpents more especially interest the zoologist because of their form, their mode of progression, and their mode of swallowing their prey. They show numerous points of structure obviously related to these peculiarities, besides other and not less remarkable anatomical characters which cannot be so explained.
Though not the highest, serpents ought perhaps to be regarded as the most specialised of reptiles; a class, next to fishes, notable for the diversity of the organisms which it includes. They are also the latest reptiles in time. The earth was already peopled with lizards, crocodilians and tortoises; ichthyosaurs, plesiosaurs, ptcrodactyles, iguanodonts and other strange mesozoic reptiles, had come and gone—before serpents made their appearance. ‘
Most serpents are inhabitants of the tropics. They are less abundant in sub-tropical and temperate regions. N 0 American species is found beyond 60° of north latitude. The most