is injurious to the colours of most green insects; and secondly, that if the specimens be not well aired after having been thus killed, the pins with which they are transfixed will become brittle and break. Insects should be left in the ammonia for several hours, and are then in the most delightful condition for setting out. To pin an insect properly is a most important procedure. The moth, if of moderate dimensions may be rested or held between the thumb and fore finger of the left hand, while the corresponding digits of the right hand operate by steadily pushing a pin through the thorax, bringing it out between the hind pair of coxæ until sufficient of the pin is exposed beneath to steady the insect in the cabinet The direction of the pin should be perpendicular when the insect is viewed from the front, as in Fig. 21; but a lateral view should show the pin slightly slanting forwards, as in Fig. 22. Pins made for the purpose in numerous sizes are sold by Mr. Cooke, of New Oxford Street. [Illustration: Fig. 21. Front View of properly pinned Insect.] [Illustration: Fig. 22. Side View of ditto.] [Illustration: Fig. 23. Cork Saddle for setting out Insects.] [Illustration: Fig. 24. Braces for setting out.] Setting out moths and butterflies is an operation which, if skilfully performed, adds much to the beauty of the future specimens. The method of setting most popular is carried out by means of saddles and braces. These so-called saddles are pieces of cork rounded as in the sectional figure, a groove being cut out for the reception of the bodies of the insects: they are generally strengthened by a strip of wood, upon which they are glued. Braces are wedge-shaped pieces of card or thick note-paper, the thick end strengthened, if necessary, with a disc of card fixed by shoemakers' paste, and pierced with a pin through it, as shown in Fig. 24. The mode of application of these appliances is beautifully shown in Fig. 26[D]. But before these straps can be applied, the wings must first be got into position by means of the setting needle and setting bristle, which are thus manipulated (the setting bristle, by the way, being formed by fixing a cat's whisker and a pin into a piece of cork, at the angle shown in Fig. 25):--After the insect is straightly pinned upon the saddle, and the legs, antennæ, and, if necessary, the tongue, got into position, the left fore-wing is to be pushed or tilted into its place by means of the setting needle, which is merely a darning needle with a handle; and simultaneously it is to be held down by the bristle; then a small brace should be applied to the costa of the fore wing. Next the hind wing should in like manner be adjusted, and as many braces as are considered necessary to keep the wings in their place should be added. Lastly, the right side of the insect should be treated in a similar way. [D] Figs. 26 and 27 have been kindly lent by Messrs. Reeve & Co. [Illustration: Fig. 25. Setting Bristle.]