In preparing to make the models, I was googling for insect models to see what others have done, and came across an article in Scientific American from 1914 about a flea model fabricated for the American Museum of Natural History in New York City.
This is an interesting article because the artist, Ignaz Matausch found that all references in books and in photographs were from dead insects. The internal organs of the insect shrink as they dry and the segments “telescope” as a consequence. As you can see, he was working under a microscope with presumably fresh specimens.
I have spent the morning looking for fresh specimens for the very same reasons. I have two friends whose kids have head lice. One has already gotten through the ordeal, so I was too late but, coincidentally, the other family called my wife and I this past Sunday for advice because they knew we had gone through an infestation of head lice several years ago. I told them what I was doing and I asked if they would collect the lice and nits in a small tuperware container and freeze them. Believe it or not, I found a container with a dried louse from our infestation two years ago that I kept to look at under the microscope, but it is not terribly useful since it is deformed from drying.
The process Matausch used is similar to what I am planning as well. He is sculpting everything in clay, making plaster molds, and casting in wax. I too, will be sculpting in clay, making silicone rubber molds, and casting in a clear polyester resin or epoxy. different materials, same process.