This 1973 image depicts two Taenia solium cysticerci, which represent the larval, or intermediate, immature developmental stages of this pork tapeworm.
Life cycle of Taenia saginata and T. solium (See PHIL 3420 for a illustrative diagram depicting the following life cycle):
Taeniasis is the infection of humans with the adult tapeworm of T. saginata or T. solium. Humans are the only definitive hosts for T. saginata and T. solium. Eggs or gravid proglottids are passed with feces; the eggs can survive for days to months in the environment. Cattle (T. saginata) and pigs (T. solium) become infected by ingesting vegetation contaminated with eggs or gravid proglottids. In the animal's intestine, the oncospheres hatch, invade the intestinal wall, and migrate to the striated muscles, where they develop into cysticerci. A cysticercus can survive for several years in the animal.