The proof I have offered that North American fish in certain lakes are infested with the larvae of D. latum has been confirmed by Vergeer, and by Essex who demonstrated the early life history in the same lake in which the larvae were found in the fish. The worm has been imported into this continent by immigrants from Europe.
The rate of growth in experimental animals has been studied.
D. parvum is identical with D. latum. It represents the worm before the terminal segments have sloughed.
Suggestions are made for the eradication of the worm from mammalian hosts.