For slide preparation, individual eggs were picked
up with fine forceps and placed on clean microscope slides. Excess
fixative was allowed to evaporate, then as small a drop as possible
of 45% acetic acid was added with a pipette, and at this stage the
egg was torn apart with fine pins. The developing tissue disaggre-
gates in the acetic acid solution, away from the fragments of egg
shell. A small drop of fixative was dropped from a pipette to spread
the cell suspension as a fine film over the slide, and it was then
allowed to dry. It is important that the drops of 45% acetic acid and
fixative should be as small as possible to avoid all the cells being
carried to the edges of the slide. Once slides are completely dry
they may be stained in 1% Giemsa stain (1% Giemsa stain in
distilled water at pH 6.8) in Coplin jars. Slides were stained for
5e10 min, rinsed in unbuffered distilled water and dried vertically.
Wet slides were examined under a low power microscope to see if
useful preparations had been obtained