Collecting and Preserving

Always keep temporary data labels with specimenson spreading boards or associated with them in some wayto insure that there is no confusion or loss of data whenthey are removed from the boards.Spreading is a highly individualistic skill, subject towide variation. Nearly everyone, with practice, evolves hisor her own technique, so that two workers may appear tofollow different procedures and yet produce equally goodresults. There is no single standardized technique withrespect to the fine points of spreading.References: Lewis 1965; Tagestad 1974, 1977.3.6 - Riker MountsIt is sometimes desirable to prepare specimens forexhibition in such a way that they may be handled freelyfor close examination without risk of damage. Rikermounts have long been used for this purpose. They may bepurchased from entomological supply houses, but similarcases may easily be constructed. The Riker mount (fig. 28)is simply a flat cardboard box about 3 cm deep, filled withcotton, and having a pane of glass or plastic set into thecover. Unpinned specimens are placed upsidedown on theglass of the cover, spread into position with some cottonheld in place by small weights, and allowed to drythoroughly (about 2 weeks). Then the weights are removed,enough cotton is added to hold the specimensfirmly in place, a little fumigant is added to kill any pestsor their eggs that might have been laid in the box, and thebottom part of the box is put in place. When the box isclosed, it should be sealed completely to prevent access toCollecting and Preserving Insects and Mitespests. Plant material may also be dried in place with thespecimens.Riker mounts are practical only for relatively largeinsects, such as butterflies, larger moths, beetles, anddragonflies, that are suitable for such display. AlthoughRiker-mounted specimens are useful for classroominstruction and general display, they are not used forstorage of insects in a scientific collection, where specimensmust be available for examination from all anglesunder magnification. Riker mounts should be inspectedperiodically for pests and kept out of sunlight, which willcause fading of colors and general deterioration.It is sometimes desirable to put pinned specimensinto Riker mounts. To do so, remove the pin or cut it offflush with the surface of the insect (see Holbrook 1927).3.7 - Inflation of LarvaeA common practice in the 19th and early 20thcenturies was to preserve larvae, mainly caterpillars, byinflation. That practice has largely been abandoned infavor of alcoholic preservation or freeze-drying. Theselatter methods permit more thorough examination of allparts of the specimens, even internal organs, which mustbe removed before inflation. Some of the colors of largerlarvae are better preserved in inflated specimens than inalcohol, but color photography has made preservation ofthe larval colors less essential. However, the technique isstill potentially useful and, if well done, is not to bediscouraged. For instructions on how to inflate larvae, thefollowing references may be consulted.References: Banks 1909 (pp.69-70); Hammond1960; Martin 1977.3.8 - Artificial DryingThe most widely used method of artificial dryingFig. 28. A Riker mount.Fig. 29. A critical point dryer and its accompanyingCO 2supply.38