the same stock may be considered as a dwarf tree, or without a stem; for the fire, by consuming the trees down to the root, produces the same effect, which amputation of the stalk would do, or as lopping on the cultivated pear or other fruit trees, which otherwise would become tall trees, but by repeated operations of pruning remain dwarfs, and produce fruit bearing branches immediately near the root. Many travellers, from want of leisure to investigate these oaks with due attention, have considered them as a particular species, but those whose acorns were sown shot forth, as well as the others, a descending small root without producing shoots; -it is therefore highly improbable, that there are oaks naturally stoloniferous or creeping.

At the present day there are numerous varieties of the oak, and to determine the species, to which they ought to be referred, is attended with much difficulty-an intermediate

termediate variety, in fact, seems to resemble two species so much, that it is frequently no easy matter, by the examination of the leaves, to determine to which of the two species this variety ought to be referred. Some species, liable to vary when young, are at this period so different, that the characters of the leaves are insufficient to determine the same species in the young oak, and the full grown one: many others, on the contrary, exhibit such an uniformity of character, that the specific distinctions can only be established on the fructification, which is itself subject to variations, and therefore exceptionable. It is by comparative observations only, on oaks in their full grown state, and when they are young, that we can succeed in distinguishing the species, which have so great an affinity to one another, and to refer the varieties to their species.

The oaks of North America have hitherto been but obscurely described, owing to

many

many reasons. In the first place, botanists, who have visited North America, give but loose and hasty observations on these trees, and besides have paid no attention whatsoever to the fructification-and secondly, by this slovenly mode of proceeding, authors have too frequently confounded many species under one and the same. denomination. In short, the plates which have appeared, of the American oaks cultivated in Europe, are by no means exact, because their growth in Europe is retarded by the climate, which is less favourable to them than that of their native country; and besides, they there preserve for a longer time the varieties of their foliage, which characterize them in their young state of growth.

Michaux, in order to satisfy himself, and clear up his doubts, sowed and culti

vated,

Many of the figures of Du Roi, and Plucknet, pl. liv. fig. 5. represent oaks, which had not acquired their full grown

state.