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IOWA ACADEMY OP SCIENCE 
Family Euglenidae. 
8. Euglena viridis Ehr. 
Very common in cultures which later developed an abundance of AmoeM 
proteus. 
9. Euglena spirogyea Ehr. 
Equally common and in cultures from the same source as the last specimen, 
with which it frequently occurred. 
10. Euglena acus Ehr. 
Only a few specimens were found in cultures of pond water. 
11. Phacus sp. 
Observed sparingly in company with Euglena viridis, but not satisfactorily 
identified as to species. 
Family Astasiidae. 
12. Astasia trichophora Ehr. 
Rare in old cultures among Algae. 
Family Paranemidae. 
13. Anisonema ludobundum' SK. 
Common in cultures from various sources. 
INFUSORIA. 
Family Echelinidae. 
14. CoLEPS HiRTUS Ehr. 
Common in cultures in which Paramaecium eaudatum appeared later. 
15. Trachelophyllum trachyblastum Stokes. 
Rare in old cultures of pond water. 
16. Didinium nastum Muell. 
Common in company with Paramaecium eaudatum, upon which it feeds. 
17. Lacrymaeia olor Muell. 
Rare in cultures of pond water. 
Family Trachelinidae. 
18. Dileptus gigas C. & L. 
Rare in old cultures of pond water. 
19. Lionotus fascicola Ehr. 
Very common among bacteria in old cultures of pond water which previously 
contained Coleps, Paramaecium, Didinium, etc. 
Family Chiliferidae. 
20. Feontonis LUCAS Ehr. 
Common with bacteria in cultures of pond water, appearing with the last of 
Paramaecium eaudatum and before Lionotus. 
Family Urocentridae. 
21. Ueocentrum turbo Muell. 
Very common in company with Paramaecium, Frontonia, etc. 
Family Paramaeciidae. 
22 Paramaecium caudatum Ehr. 
Very common in cultures of pond water. 
23. Paramaecium bursaria Ehr. 
