subjects of natural history. From that time I took care to delineate none that I was conscious had engaged the pencil of any preceding author; but confined myself to such, whose novelty and striking appearances could not fail to recommend them. To such non-descripts I have paid the greatest deference; for in some of the plates, among the butterflies and moths, I have given complete figures of both the upper and under sides; a practice that, as deviating from my general rule, I should not have done, if the richness and softness of the colouring had not been so extremely pleasing, as to render it scarcely possible to dispense with it. It is only to a few I have paid this particular respect. In general, I have given to the butterflies, only figures of one half their under sides, but whole upper ones; and of those moths that have no representations of their under sides, the reader may conclude there is no material difference between their upper and under ones, or else the latter is too poor and mean to justify the giving a figure of it. I must just mention, that although I used this forbearance to those figures that had been heretofore published, I by no means meant to debar myself from representing such as had been only _verbally_ described; as is the case with a great many to be met with in the Systema of Linnæus, and in other authors. The refraining, therefore, from such subjects, would have been rather condemnable than fit to be approved, for the reasons I mentioned before, of the great difficulty there is in understanding, sometimes, the best verbal descriptions that ever were given; therefore figures of this kind may not improperly be considered as explanatory, or as illustrations to {xxii}such verbal descriptions, affording the student a two-fold pleasure, by comparing them together.