Canine Tapeworm Scolex
The proglottids pass through the digestive tract of the primary host and are eliminated with feces. Intermediate hosts (generally prey animals) ingest the larval forms when grazing on contaminated grass. Once ingested, the larvae emerge in the digestive tract where they burrow through the intestinal wall into a blood vessel and are carried to muscle tissue or some other organ tissue (various species of tapeworms select different tissues as destinations for the larvae). The period during which the larvae are encysted in the tissue of the intermediate host is known as the cysticercus, or bladder worm, stage.