"Although," he continues, "we would greatly restrict the limits of the study, there are persons who will think them still too wide; there are even some who consider all knowledge of this part of natural history as useless, and who unhesitatingly pronounce it a frivolous amusement. We are equally willing that these pursuits should be regarded as amusements, that is, as studies which, so far from being troublesome, afford pleasure to the person who engages in them. They do more,--they necessarily raise the mind to admire the Author of so many wonders. Ought we to be ashamed of ranking among our occupations observations and researches, of which the object is an acquaintance with the works on which the Supreme Being has displayed a boundless wisdom, and varied to such a degree? Natural history is the history of his works; nor is there any demonstration of his existence more intelligible to all men than that which it furnishes." The two first volumes treat of caterpillars, their forms and habits, their metamorphoses into butterflies, and the insects which attack them, or which live within their bodies. The third speaks of the small creatures named moths, which exist in the interior of the substances which they devour, or form of them coverings for their protection. It also contains the history of the aphides, a very numerous race of small insects, which suck the juices of trees and plants, live in society, and are often productive of great damage. These animalcules are especially remarkable for their mode of generation; it having been proved by M. Bonnet, that a single impregnation is sufficient for the production of many successive generations, and that they are viviparous in summer and oviparous in autumn. The flies which produce the excrescences named gall-nuts, and the worms from which come the dipterous insects, so diversified in their forms, manners, and places of abode, occupy the fourth volume. The fifth contains, among other genera, the bees, of which the history is so singular and interesting. Certain varieties of these as well as wasps are described in the last volume. Similar researches were made by Bonnet and De Geer, of whom we shall have occasion to speak in another part of our series. Reaumur was the first naturalist who formed an extensive collection of animals in France. The celebrated Brisson, who was the keeper of his museum, derived from it the principal materials for his works on quadrupeds and birds. These last afterwards constituted the basis of the Royal Museum at Paris.