| Procedure: |
| 1. |
After removing any sealant material soak Hoyer's-mounted
specimens in Petri dishes with distilled water, for about 60 hours. |
| 2. |
Transfer specimens to 10 % ethanol in a ceramic depression
plate and cover the specimens with coverslips. |
| 3. |
Replace ethanol with 10 % KOH and leave the specimens for
30-40 minutes at room temperature. KOH is not only a clearing and softening
agent, but this treatment reduces antennal collapse after transfer to
balsam. |
| 4. |
Remove KOH with a pipette and replace with 10% ethanol and
leave for 30 min. Repeat this step with 20, 40, 60, 80, 95 and 100 % ethanol
(use 100% ethanol - twice for the best dehydration). |
| 5. |
Replace the 100 % ethanol with a mixture of ethanol and
clove oil (50 %: 50 %) and put the ceramic depression plates into a partly
opened container for 2 - 3 weeks. Complete water and alcohol evaporation
are critical: the presence of even a small quantity of water or alcohol
results in partial or complete collapse of the antennae. |
| 6. |
Remount specimens on slides using Canada balsam mixed with
15 % clove oil. The use of xylene at this stage, results in antennal collapse.
Cover with clean dry coverslips. |
| Using this method results in about 80-95 %
of the specimens having normal heads and antennae, with little or no collapse.
Wash all tools (hooks, pins, tweezers) with turpentine, which is much
less harmful than xylen. |