
438 THE AMERICAN NATURALIST. (VoL. XXXVI. 
in the water. The larval integument with its cilia and flagella 
is apparently shed, as described by van Beneden (61) and 
Dieck (74). At this time the embryos assume the form of the 
adult and crawl about instead of swimming. The integument 
of the young worms now becomes covered with cilia, as in the 
adult. After remaining for a time among the egg masses of 



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Fic. 2. DU agone, section through anterior portion of body of C. eren Trees. diagram- 
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the host, or perhaps until her eggs have hatched, they wander 
about on her body, eventually reaching the gills. They are 
found in this position in July or August, and later, and here 
they probably remain until the crab produces another batch of 
eggs the following season. At this time they migrate again to 
_ the egg masses, where they become sexually mature. Those 
