26 College of Forestry 
SUM MARY. 
1. The physiographic conditions of the several ponds studied do 
not explain the distribution of parasites in the perch. The extensive 
distribution of Clinostomum marginatum indicates that a wide range 
of conditions allow the adult to reach maturity. 
2. The general form and appearance of the so-called adult worm as 
found in birds does not differ from those taken from the cysts of 
the perch, 
3. The brownish bodies found in the liver of the snail and the 
minute cysts found in the muscles of the perch suggest that this rep- 
resents part of the life history of Clinostomum marginatum. 
REFERENCES. 
Braum, M., 1900. Die Arten der Gattung Clinostomum Leidy Zool. 
jahrb. syst. bd. 14 p. 1. 
Cort, William Walter, 1913. Notes on the Trematode genus Clinos- 
tomum. Trans. Am. Micr. Soc. vol. 32, July, no. 3, pl. IX, p. 169 
Gamble, F. W., 1910-11, Trematodes. The Encyclop. Brit. Eleventh 
edition vol. 27, p. 240. 
Heckert, A., 1889. Untersuchungen tiber die Entwicklungs und Leben- 
geschichte des Distomum macrostomum, Cassel. Bibliotheca. Zoologica, 
linter4a tare 2) sp. 100% 
Linton, E. R. 1898. Notes on the trematode parasites of fishes. 
IRFOCU AS sNats Mitts) vol 10. p: 507. 
1910. The diagnosis of a case of parasitism in the brook 
trout. Proc. Seventh Inter. Zool. Cong. Boston meeting, 1907. 
Loess, A. 1885. Beitrage zur Kenntniss der Trematode Distomum 
palliatum n. sp. und D, reticulatum n. sp. Zeit. f. wiss zool. bd. 41, 
p. 390. 
1892. Ueber Amphistomum subclavatum Rud. und seine 
Entwicklung, Festschrift z. 70 Geburstage R. Leuckart’s, Leipsic taf. 2 
p. 147. 
MacCallum, W. G. 1899. On the species Clinostomum heterostomum. 
Jour. Morph. vol. 14 p. 97. 
