Light micrographs of helicosporidial cells produced in vitro. Actively growing culture of the Helicosporidium sp.

Light micrographs of hemolymph sampled from Manduca sexta larvae infected with Helicosporidium sp. Two days postinfection extracellular vegetative helicosporidial cells and normal looking hemocytes.

Six days post-infection plasmodial-like hemocytes displayed cytopathic effects.

Ten days post-infection. Note the number of refractile cysts and vegetative cells as compared to the numbers of hemocytes.