The males of many kinds of butterfly have special scales, which are known as androconia, or plumules. It is believed that these are scent organs. Whatever their particular use may be to the possessor, these androconia enable the entomologist to distinguish male specimens from females with great certainty. In the Fritillaries they are placed on one or more of the median nervules (veins 2, 3, and 4) of the fore wing. In the Meadow Brown and its kindred they form brands on the disc of the fore wing. In the Skippers they are placed in a fold of the costa in some species, and in other species they are clustered together, into more or less bar-like marks, about the middle of the fore wings. Some of these various shaped "plumules" are shown in the illustrations. In the foregoing sketch of the life cycle of a butterfly, the object has been to condense as much necessary information as possible into a limited space. Many matters of importance to the student have not been touched on, but it was considered that, as these were more especially connected with a higher scientific phase of the subject than would here be found helpful, they might be omitted. [Illustration: FIG. 11. =Butterfly Plumules.= _a._ Tufted Plumule (Satyrs); _b._ Bristle Plumule (Grizzled Skipper); _c._ Hair Plumule (Dingy Skipper); _d._ Jointed Plumule (Silver-studded Skipper); _e._ Bladder Plumule (Common Blue); _f._ Dotted Plumule (White-letter Hairstreak). (_After Aurivillius._)] Collecting. Naturally the first matter for consideration, when the formation of a collection of butterflies has been decided upon, is how to set about it. Well, there are two methods of effecting our purpose. The specimens may be purchased from a dealer in such things, or we may acquire an outfit comprising net, boxes, and pins, and go in search of the insects ourselves. Apart from its healthful and entertaining possibilities, the latter method has very much to recommend it. In the first place, those who are at all observant--and no true lover of Nature can be suspected of being otherwise--will become acquainted with the objects under natural conditions, and so be enabled to appreciate them more highly than could be the case if they were obtained in any other way. The chief purpose in making a collection of Natural History specimens should be study of some kind rather than mere accumulation. [Illustration: FIG. 12. =Y-piece.=] [Sidenote: Nets.]