IOWA ACADEMY OF SCIENCE 
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Boone, Davenport, and contributions have been received from Alla- 
makee and Fayette counties. As before noted only a small part of 
these collections have as yet been thoroughly worked over, and 
the remainder awaits our leisure for further study. 
Most collections were made in small vials, and preserved in 2% 
formalin solution. This seems particularly adapted to the preser- 
vation of the algae, they remain almost of the normal color and 
retain their shape well for several years at least. 
Methods of Study. Most of the material studied was mounted 
in a weak solution of formalin to which had been added a small 
amount of eosin, the mount then ringed. If the ringing is successful 
the slides may be preserved for several years at least without 
change. The eosin is very satisfactory as an aid in the determina- 
tion of the details of structure. 
Authorities on Identification. As a guide to the identifica- 
tion of the genera of the forms studied, and to the recognition of the 
great groups of algae, West’s “British Freshwater Algae” has been 
of the most material assistance. The order in which the various 
genera are given in the. list has been adapted from this work, and 
the same work has furnished a basis for the majority of the keys 
that are given therein. The section of Engler and Prantl’s Pflanzen- 
familien devoted to algae has also been of material assistance in the 
construction of keys, etc. For description of species in general 
De Toni’s “Sylloge Algarum” has been used, together with Raben- 
horst’s “Kryptogamen Flora,” and Kirchner’s “Algen von Schlesien” 
and more particularly Wolle’s “Freshwater Algae of the United 
States” and “Desmids of the United States” in some groups and 
genera. The same may be said of “Cooke’s British Freshwater 
Algae.” “The Ulothricaceae and Chaetophoraceae of the United 
States” by Tracy Elliott Hazen was used in part in the determina- 
tion of the species of these groups. “Protophyta and Phycophyta” 
of the flora of Nebraska published by the Botanical Seminar of 
the University and written by De Alton Saunders has proven of 
considerable comparative interest also. Bornet and Flahault’s 
“Revision des Nostocacees Heterocystees” was also consulted for 
determination of species described therein. The lists of the Algae 
of Minnesota published by Miss Tilden have also been consulted 
with considerable interest, inasmuch as much of the northern part 
of the state should have about the same algal flora as a large section 
of Minnesota. 
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