As already hinted, there are times when it is desirable to take home certain butterflies alive, either for a study of their movements or for the purpose of securing eggs for breeding. To this end you must provide yourself either with a number of 'chip boxes' with a few small holes pricked in the cover, or with some metal boxes with perforations for the admission of air. If the latter, you will have no difficulty in securing a few 'tin' boxes of suitable size, but, as the surface of the metal is very smooth, you should always introduce a few leaves or something else that will provide a foothold for the inmates. The last item of the outfit is the pins. Ordinary draper's pins are quite out of the question. They are far too thick and clumsy for the collector's work. If you are not already acquainted with the 'entomological pins,' you had better ask a dealer to give you a sample card. This will be very useful for reference until you become well acquainted with the various lengths, thicknesses, numbers and prices. The card will contain one of each kind, with price and number attached. If you fix a butterfly with the ordinary pin, you may find the latter partly covered over with verdigris after a time. This bright green substance is formed by the action of decomposing animal matter on the copper of the pin, and gives a very unsightly appearance to the specimen. To avoid this the entomological pins are either silvered, blackened or gilded. The silvered pins tarnish after a time, but the two other kinds keep their colour well, and are therefore better. The gilded ones are rather expensive and unnecessary, and perhaps the black ones are to be preferred to the silvered, although they are rather more costly. Most dealers will supply you with a box of mixed pins, each box containing about six different sizes. This is very convenient for those who work in a rather small way; but if you intend to make entomology a prolonged study you had better get an ounce or so of each of the more useful sizes. Butterflies vary much in size, and Nos. 3 to 8 are the most useful sizes of pins to fix them; No. 3 being for the largest, and 8 for the smallest. Supposing all the foregoing requisites to be quite ready, still you are really by no means prepared for all your work. The butterflies captured should be set as soon as possible after your return, and everything required for _this_ part of the work must be in perfect trim. Yet I think it will be more convenient just now to confine our attention to the subject of 'Catching Butterflies,' leaving all the indoor work to form the substance of another chapter. Our next point, then, shall be the consideration of seasons, times, and localities.