224 THE AMERICAN MONTHLY [ December, 
confirmed indirectly by these results. They throw no light, however, on 
the supposed relation between cholera nostras and the spirillum of Finkler 
and Prior. 
Internal parasites of teredo navalis. 
By W. F. DURAND. 
AGRICULTURAL COLLEGE, INGHAM CO., MICH. 
In the autumn of 1886 a large float at the Norfolk navy yard was hauled 
out of the water for repairs. 
On stripping off the old bottom it was found to be badly attacked by the 
mollusk Zeredo navalis, the so-called ‘ ship-worm.’ Many of them were 
found in their burrows, and, thinking that they might prove interesting for 
microscopical examination, a number were collected for that purpose. 
Remembering the wonderful series of internal parasites of the white ant, 
and Leidy’s statement that wood-boring and wood-feeding animals are apt to 
be infested with such parasites, it seemed at least possible that some such forms 
might be found within the ¢teredo. 
Examination proved the correctness of the supposition, showing various 
forms, as represented in the accompanying sketches. 
PARASITES OF Jeredo navalis. 
a 
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