The person requesting the work is interested in eye morphology. Working in the medical field, I have never embedded a sample with an exoskeleton before and am wondering if someone out there can give me an idea on the appropriate fixatives to use including fixation times and any little tricks I may need to know. Veronica Andrea Campanucci Laboratorio de Fisiologia de Insectos Dpto. It helps to cut the proboscis off if you are not allowed to bisect the head. Proper orientation can be the most difficult often requiring two or more embeddings, reorienting each time.
Some people leave the head attached to the body for ease of handling.
This assumes that the client isn't investigating something in the eye that changes subtly with tanning, or age after emergence. The most difficult part of the eye for TEM are the crystalline cones. If possible, before fixation or embedding. The easiest way to do this is chopping away with a glass knife after the blocks are ready. You can handle the retinal tissues pretty much like any neural tissue.