These lobes are cut longitudinally. Ideally each section of a single
lobe contains practically all of the maturational steps in sperm development.
These sections are missing the initial stage, spermatogonia. These testis
consists of many lobes, the pointed ends open into the vas deferens, or sperm
ducts. Each lobe contains many cysts, separated from each other by connective
tissue partitions or septa. These cysts are composed of cells in the same stage
of development. At the blunt or apical end of the lobe there are many small
primordial germ cells, each known as a spermatogonium, and all undergoing
mitosis. This mitotic activity produces the cysts. From the blunt to the
pointed end the cysts show progressive stages of maturation. Differentiating
and mature spermatozoa can be seen where the lobe is to join the vas deferens.
These testis are from the lubber grasshopper, Rhomaleum
