. Elementary lessons on insects. Insects. 190 ELEMENTARY LESSONS ON INSECTS do it at the first trial. The specimens, whether whole minute insects, or minute parts of larger insects, are first soaked in strong alcohol until the water is extracted from them. Two changes of 95% alcohol may be required for this, with a stay of some 5 to 10 minutes (longer if impervious) in Fig. 68.—Diagram illustrating a method of making slide mounts. Specimens are prepared on the stage of a dissecting microscope, A; then soaked in strong alcohol in the watch glass, B; then cleared in carbol-turpentine in t
. Elementary lessons on insects. Insects. 190 ELEMENTARY LESSONS ON INSECTS do it at the first trial. The specimens, whether whole minute insects, or minute parts of larger insects, are first soaked in strong alcohol until the water is extracted from them. Two changes of 95% alcohol may be required for this, with a stay of some 5 to 10 minutes (longer if impervious) in Fig. 68.—Diagram illustrating a method of making slide mounts. Specimens are prepared on the stage of a dissecting microscope, A; then soaked in strong alcohol in the watch glass, B; then cleared in carbol-turpentine in the second glass, C; then placed at x on the glass slide, D, on which there has been placed a drop of Canada balsam from the bottle E. Then the coverglass is added and a gummed label attached. Then they are transferred to carbol-turpentine or carbol- xylol.* This is a clearing agent. It replaces the alcohol and prepares for balsam. Then they are transferred from the clearer with a forceps to a drop of Canada balsam that is first placed on a slide. In the balsam they are then arranged in proper position, and a thin cover glass is lowered over them. When the balsam has spread out evenly to the margins of the cover glass, filling the space underneath completely, the mount is finished, f It should then be * A mixture of 1 part of carbolic acid (pure phenol crystals) to 3 parts of either turpentine or xylol. f Small air bubbles, if accidentally included, will escape of themselves slowly. More balsam, if needed to fill the space, may be added at the edge of the cover; The specimens should be placed well within the margin of. Please note that these images are extracted from scanned page images that may have been digitally enhanced for readability - coloration and appearance of these illustrations may not perfectly resemble the original Needham, James G. (James George), 1868-1956. Springfield, Ill. , Baltimore, Maryland, C. C. Thomas
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Keywords: ., bookcentury1900, bookcollecti, bookdecade1920, booksubjectinsects
