again, especially if the stopper is wet. Fill your collecting vials about two-thirds full, to allow plenty of room for both specimens and air space. If, through a shortage of bottles or the unavail- ability of small ones, you should find it necessary to put more than one group of specimens in a container, be careful to keep them well separated from each each other, and inseparable from their proper label. When using a wide mouthed jar, tie up each lot, with its label, in a small twist of cheese cloth. Partition a tall narrow bottle with plugs of cotton or soft paper. To facilitate subsequent unpacking, put two distinct wads between each two successive layers of specimens, so that, should the claws of the creatures become entangled in the fibers, you will not have members of two lots clinging to opposite sides of the same bit of packing. covered. In buying a vest for this purpose, insist on complete pockets, closed at the bottom, and be sure to use vials that fit them precisely, so as not to fall out when you bend over. Insects sufficiently hard-bodied to be mounted upon pins are usually killed in a dry killing bottle, and all hairy or scaley ones, moths, butterflies, and true flies especially, must be so collected unless in- tended for dissection. The construction and use of the Ethyl-acetate or Ether type of killing jar is discus- sed in Leaflet Number 1; the traditional cyanide jar in Number 7. Although such bottles anesthetize an insect quickly, resistant species may revive if removed less than half an hour after capture. It is unwise to overcrowd a jar, both because the creatures may damage each other while still squirming and because the accumulated moisture from a large lot may con- dense on the inside of the bottle and stain the speci- mens. Consequently, on a collecting trip of any duration, it becomes necessary to carry several killing jars to be used in rotation. It will also be advantage- ous to provide jars of various sizes, so that small and delicate species need not be lost or damaged among the large and durable specimens in a common jar. For a day's collecting you might use one half-pint bottle, for very large specimens; two four-ounce bottles, for those of average size; and several four-dram vials for the very small. Moths and butterflies, being prone to shed their scales, must have a special bottle of their own which is not used for other insects. Since you should never touch them with your fingers, you are not likely to take many Lepidoptera by hand- collecting, although it is possible to knock a sleeping moth into the killing jar without picking it up, or to capture an occasional butterfly by the bottle-and-card technique. Similar precautions should be observed with flies, especially the very hairy ones, the handling of which is described below under "Aerial Collecting." Fig. 1. Using the wet brush to handle minute insects. Many of the insects and spiders collected into alcohol are too small to be grasped with the fingers, and too delicate to be siezed with forceps without danger of crushing. These may most easily be captured by use of a camel's hair brush. A number one or two round water-color brush is perfect. Moisten the brush with killing fluid and sweep up the specimen with its tip, using a sideways prying motion if the creature is tenacious. Once it has released its grip, the specimen will adhere to the wet bristles until it is washed off in the collecting vial. In a pinch the tip of the forceps or the end of a twig can be employed in the same manner. Although small bottles of alcohol can be carried loose in the pocket with comparative safety, those who specialize in this kind of collecting sometimes use a hunter's vest, carrying one vial in each of the car- tridge pockets with which the front of the garment is Specimens should be left in the killing jar no longer than necessary, since prolonged exposure to the lethal fumes may cause discoloration, and the constant agitation to which the bottle is subjected in the field may so batter the catch that it cannot be identified. Only experience can teach you how many specimens a killing jar can safely accommodate, and for how long, but from time to time you should stop adding insects to a bottle, and about half an hour later transfer its contents to a storage box for safer transpor- tation. The simplest effective field storage box is a strong, tight, pocketsize container filled snugly with layers of thin glazed cotton or cellulose packing material cut to fit exactly. Fill this box from the bottom up, placing the specimens, one deep, between the layers of cotton, and always replacing all the packing before closing the lid, so that the specimens cannot bounce around