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Some Points on Methods of Collecting Different Orders

Hymenoptera.--Many Hymenoptera, such as the bees, some of the wasps and many parasitic forms, can readily be collected by means of the beating net or sweeping net from flowering plants. The removal of the stinging species from the net is sometimes rather dangerous. The callous collector will pick them up with his thumb and fore finger, never minding the sting, especially as after a few stings his hand becomes practically inoculated, but a good idea is to have an opening in the bottom of the net which should be kept tied with a string. When enough insects are caught they are driven to the bottom by swinging the net rapidly through the air, then holding it tightly together with the hand just above the bottom, untieing the string and shaking the insects into a wide-mouthed cyanide bottle. After they are stupefied the contents of the bottle may be emptied out and the desirable specimens selected. The gall-flies and the parasites are best collected by breeding. The galls of the gall-flies should be collected when mature and kept in closed jars, the jars being occasionally moistened by putting a sheet of damp blotting paper over the mouth.

Hemiptera.--The beating net is used with these insects and they are found to some extent under logs and stones and are also captured in the collecting umbrella. Plant-lice should be collected in connection with their food plants and at different seasons of the year in order to obtain different generations. One should also collect both winged and wingless forms. Bark-lice or scale insects should be preserved dry in situ on the plants. The collector should have a series of small envelopes or flat card boxes in which to place these specimens, writing the date, locality, name of plant, collector, and any other remarks that may seem desirable. Nothing air-tight, such as tin boxes or closed tubes, should be used for fresh material as it nearly always molds. Pill-boxes are sometimes used but are too small to contain a good quantity of material. A good-sized twig or several leaves should be collected for each species.

Diptera.--Most flies frequent flowers and may be collected with the sweeping net. So many of them are very delicate that the greatest care must be exercised both in collecting and handling. A light sweep net is the best implement and the contents should frequently be emptied into cyanide bottles with plenty of blotting paper to absorb the excess of moisture. Collecting shears are successfully used with these insects.

Orthoptera.--These insects are best collected by using the sweeping net.

Collecting Aquatic Insects.--For collecting forms which live upon the bottom of ponds and streams, Dr. Needham advises the use of the common garden rake. With it the debris may be drawn ashore and the insects picked out by hand. Withdrawn from the water they generally make themselves evident by their active efforts to get back. The rake is especially useful in the spring while there is as yet no new growth of well-rooted water weeds to interfere with hauling it. The sieve net previously described is used for bringing ashore mud and sand from the bottom. Those specimens which live above the bottom in still or slowly running water or which crawl among the submerged branches or erect aquatic plants are most of them easily taken by sweeping the plants with any of the forms of water nets. Some of the little ones which cling closely to the water plants can only be discovered by taking the plants out of the water and examining them, a small bunch at a time, in a white dish of clean water. Those forms which live in rapids can be had by picking up the stones and examining them. Some may be taken with a water net. Some are captured by wading into the rapids holding the water net with the left hand and lifting the stones in advance with the rake, the disloged insects floating into the water net.

In carrying home a day's catch a large quantity of water is not necessary. Needham says that it is well to have a pail and to place within it a few smaller receptacles containing a little water and pack ordinary water weed between these. The smaller nymphs taken may be distributed among these receptacles so as to diminish the chances of having them eaten by the larger and stouter ones which may be stowed away in the weed. The latter does not need to be submerged unless left long uncovered in the sun.