IOWA ACADEMY OF SCIENCE 
67 
Filaments fine, involved in tufts in dense gelatinous substance 
2. Chaetophora 
Filaments and main branches larger, bearing dense fascicles of small 
branchlets 3. Draparnaldia 
1. Myxonema ( Stigeoclonium ) 
KEY TO THE SPECIES. 
Opposite branching predominating. 
Filaments 11-30 u in diameter M. flagelliferum 
Filaments 7-10 u in diameter M. tenue 
Alternate branching predominating, diameter 6-8 u . .M. nanum 
7Jf. M. fiagelligerum (Kutz) Rabenh. 
Iowa City. Hobby. 
75. M. tenue (Ag.) Rabenh. 
Iowa City. Hobl/y. 
Ames. Main effluent filter beds. Buchanan. 
76. M. nanum (Dillw.) Hazen. 
Fayette. Fink. 
Grinnell. Fink. 
Ames. College Spring. Buchanan. 
2. Chaetophora. 
KEY TO THE. SPECIES. 
Colonies of filaments subglobose or tuberculose. Branching erect, fas- 
ciculate at the summit C. pisiformis 
Colonies of filaments extended, irregularly lobed or laciniate 
C. incrassata 
77. C. pisiformis (Roth) Agardh. 
Iowa City. Hobby. 
West Okoboji. Common. Shimek. 
Fayette. Fink. 
Eagle Grove, Jenning’s Pond. Buchanan. 
Ontario Pond. Buchanan. 
Ames. Pond near R. R. Buchanan. 
78. C. incrassata (Hudson) Hazen. (cornu-damae) . 
Fayette. Fink. 
Allamakee Co. Pammel. 
79. C. monilifera Kutz. 
Clear Lake. On Cladophora. Shimek. 
3. Draparnaldia. 
KEY TO THE SPECIES. 
Rachis clearly traceable to or beyond the summits of the fascicles of 
branches D. plumosa 
Rachis soon lost in the ramifications of the orbicular spreading fascicles 
' D. glomerata 
80. D. plumosa (Vauch.) Agardh. 
Ames. Bessey. 
Fayette. Fink. 
81. D. glomerata (Vauch.) Agardh. 
Iowa City. Hobby. 
