difficulties formerly alluded to, and partly to the vast extent of the subject. Let any one attempt to arrange and name a moderate sized collection of foreign moths, and he will soon be convinced how little has been done to facilitate his labours. The system of Latreille, one of the few that professes to apply to the whole subject, may now be regarded as little more than an outline, which leaves a great mass of the species altogether unprovided for. Hence the necessity that continually arises, even when giving the history of a comparatively limited number of species, for the establishment of many new genera. It must be admitted that such a step, in regard to insulated species, and when there is no means of distinctly pointing out the limits and relations of the genus so constituted, is in some degree unsatisfactory; and it becomes even more so when the genus is formed, as is sometimes necessarily the case, from the mere inspection of an engraved figure, destitute of those details of structure which should enter into the generic definition. But when it is found that the insect thus distinguished cannot with propriety be included in any of the existing genera; that it affords prima facie grounds of distinction which cannot be overlooked, there is no alternative but to adopt this course. It is at least advancing on the right path, although the progress may not be so considerable as might be desired.
There are few departments of entomology more worthy of the attention of travellers in foreign countries than that now under consideration. Scarcely
