The remainder of its story is not easily discovered. It is now the beginning of April. My three children, the joy of my declining years, lend me the keen sight of youth. Without their assistance I should abandon all thought of the chase, which I now propose to pursue on the confines of invisibility. The previous year certain thickets of evergreen oak, well within the reach of the observer, were marked down as being thickly peopled by the Kermes. At that time I marked every populated twig with a white thread. It is here that my little collaborators patiently pursue their investigations, leaf by leaf, and twig by twig. After a brief glimpse through my lens the harvest is placed in a botanist’s specimen box; a more scrupulous examination will be made in my study, with all the conveniences which the observer may require. On the seventh of April, just as I am beginning to despair of my investigations, the tiny insect crosses the field of my pocket microscope. This is she, actually this is she! Just as I saw her last year emerging from her natal shell, so once more I behold her now. No change whatever is visible: neither of aspect, nor shape, nor colouration, nor size. She goes bustling along as though busy in the extreme, searching doubtless for a spot to her liking. At every moment the smallest wrinkle in the bark conceals her from sight. I place the twig that bears the precious atomy under a bell-glass. On the following day I expect a moult. The bustling little insect is replaced by a motionless corpuscle. This is the first stage of the globular Kermes. Fortune has only once vouchsafed me such a “find,” which would have been examined in greater detail had I possessed a sufficient number of subjects. My inspection of the evergreen oaks was somewhat in arrears; I ought to have made it in March. At this period, I imagine, I should have caught the insect emerging from the soil and returning to the foliage of its oak-tree, in order there to undergo transformation. Instead of one single subject I should have had many, though even then I could not have counted upon a numerous collection, for the hardships of winter have certainly thinned out those families, which were in the beginning so numerous. They descended from the tree in their hundreds of thousands; they climb it again in scanty groups, as is attested by the scarcity of the black globules in the warm weather. As for what becomes of the climbers, my single specimen tells us plainly enough. It has become a spherical speck, the indubitable sign of the future Kermes. In a few days’ time it has dried up, despite the glass of water into which the base of the twig was immersed. Fortunately I have a few other similar corpuscles, a little more developed. My gleanings give me two kinds of corpuscle.