Creepy, Crawly Creatures from the Deep...
The above critters (called protoscolices or "hydatid sand" of Echinococcus species tapeworms) are from the small cysts below. The shark-teeth-looking things inside them are called hooklets, and like shark teeth, are designed to dig in and hang on to the inside of your intestinal wall. The cysts below are only three of many cysts removed from a larger "mother" cyst from the liver and stomach of a 57-year-old. The cyst may have been growing for 30 years or more before causing any symptoms in the patient.
Don't worry...Echinococcus species are "incidental parasites" for humans (meaning they'd much rather be in their natural host, in this case dogs or sheep, than in you!) For symptoms and clinical features, read more here.