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Show 5SZ 1';'1'. HB LEN.\. July, 1836. from below, so that the confusion in structure from these different causes is extreme. On the higher parts of the island considerable numbers of shells occur embedded in the soil, which have always been supposed to be of marine origin : and the fact has been adduced as a proof of the retreat of the sea. The shell turns out to be a Bulimus, or terrestrial species. It is however very remarkable, that it is not now found in a living state: a circumstance which in all probability may be attributed to the entire destruction of the woods, and consequent loss of food and shelter, which occurred during the early part of the last century. The history of the changes, which the elevated plains of Longwobd and Deadwood have undergone, as given in General Beatson's account of the island, is extremely curious. It is said the plain in former times was covered with wood, and was therefore called the Great Wood. So late as the year 1716 there were many trees upon it, but in 1724 the old trees had mostly fallen ; and as goats and hogs were at that time suffered to range about, all the young trees had been devoured. It appears also from the official records, that the trees were un~ expectedly, some years afterwards, succeeded by indigenous wire grass, which now spreads over its whole extent.* He then adds, "These are curious facts; since they trace the changes which this remarkable spot of land has undergone, for now this formerly naked plain (after the trees had fallen) is covered with fine sward, and is become the finest piece of pasture on the island." The extent of surface, which was probably covered by wood at a former period is estimated at no less than two thousand acres ; at the present day scarcely a tree c.a~ be found there. It is said, that in 1709 there were quantltles of dead wood in Sandy Bay : this place is now so utterly desert, that nothing but so well-attested an account could make me believe that trees had ever existed there The fact, that the goats and hogs destroyed all the youn~ trees as they sprung up, and that in the course of time ',¥: Beatson's St. llclena . lutmductory chapter, p. iv. July, 18.36. C11A~GES lN VEGE'fA'l'lON. 5~3 the old ones, which were safe from their attacks, perished from age, seems clearly made out. Goats were introduced in the year 1502; eighty-six years afterwards, in the time of Cavendish, it is known they were exceedingly numerous. More than a century afterwards, in 1731, when the evil was completed and found irretrievable, an order was issued that all stray animals should be destroyed. When at Valparaiso, I heard it positively affirmed, that the Sandal-wood tree had been found on the island of Juan Fernandez in considerable numbers, but that all without exception were standing dead. At the time, I thought it was some mysterious case of the natural death of a species ; but when it is remembered, that goats for very many years have abounded on that island, it seems most probable that the young trees were prevented growing, and that the old ones perished from age. It is a very interesting fact, to observe that the arrival of animals at St. Helena in 1501 did not change the whole aspect of the island, until a period of tlrYO hundred and twenty years had elapsed : for they were introduced in 1502, and in 1724 it is said "the old trees had mostly fallen." There can be no doubt, this change affected not only the Bulimus and probably some other land shells (of which I obtained specimens from the same bed), but likewise a multitude of insects. St. Helena, situated so remote from any continent, in the midst of a great ocean, and possessing a unique Flora,-this little world within itself,-excites our curiosity. Birds and insects,* as might have been expected, are very few in number; • Among these few insects, I was surprised to find a small Aphodius ( no1J. spec.) and an Oryctes, both extremely common under dung. When the island was discovered it certainly possessed no quadruped, excf:pting perhaps a mouse; it becomes, therefore, a difficult point to ascertain, whether these stercovorous insects have since been imported by accident, or if aborigines, on what f6od they formerly subsisted. On the banks of the Plata, where, from the vast number of cattle and horses, the fine plains of turf are richly manured, it is vain to seek the many kinds of dung-feeding beetles, which occur so abundantly in Europe. I observed only an Oryctes (the insects of this germs in Europe geneJally feed |