238 College of Forestry 
(1903, p. 158) states that ‘‘ The crayfish, eel, shrimp, fresh- 
water mussels and probably such tender-shelled bivalves as 
are found in the bays frequented by them are also eaten.” 
To what extent shellfish are eaten is not known. 
9, Parasrres Arrecting Moxmuusks. 
Fishes suffer to a marked degree from the attacks of para- 
sitie worms and Protozoa. ‘These include tapeworms, flukes, 
and other worms which infest the stomach, liver, intestine, 
eyes, and other parts of the body. A great many worms 
infest fresh-water mollusks. In a few cases the mollusk is an 
intermediate host of some worm that completes its develop- 
ment in other animals. Only those parasites will here be 
considered that have been reported as living in the species of 
fresh-water mollusks inhabiting the State of New York (cf. 
Leidy, 1858-1904). The list is sufficiently full to emphasize 
the importance of the subject. ‘The parasites here mentioned 
have been accumulated rather incidentally and are listed as 
follows by authors: 
Anoplophyra vermicularis Leidy. Infusorian. 
This infusorian infests the rectum and intestine of Cam- 
peloma decisum, often in great numbers (Leidy, 1877, b, p. 
260). 
Tetracotyle tipica Diesing. 
Encysted in liver and genital gland of Galba catascopium 
and Physa heterostropha (Leidy, 1904, p. 237). 
Monostoma (Glenocercaria) lucania Leidy. Fluke. 
Infest intestine, liver and muscular tegument of 
Planorbis parvus. As many as 50 sporocysts distended with 
cercarize have been taken from a single Planorbis (Leidy, 
1877, a, p. 200). 
Distoma (Gymnocephala) ascoidea Leidy. Fluke. 
Infest liver and intestine of Planorbis parvus (Leidy, 
18774, pe 201): 
