APHANOCHAETE A. Braun 1851, p. 196 

 [Herposteiron Naegeli in Kuetzing 1849, p. 423] 



Thallus composed of a creeping, irregularly branched (rarely un- 

 branched) filament of cylindrical or inflated cells which bear 1 or 

 more long setae with a bulbous base, the setae without a sheath and 

 arising from the upper free walls. 



Species in this genus are usually found on other filamentous algae, 

 one in particular being confined to filamentous desmids. Differentia- 

 tion of species cannot be made with certainty unless the plants are 

 well developed. 



Key to the Species 



1. Filament arched; in contact with the host 



only at intervals A. vermiculoides 



1. Filament creeping on the host; in contact 



throughout its length or nearly so - 2 



2. Cells bearing 2—6 setae (rarely 1), 9— 15m in diameter A. polychaete 



2. Cells bearing but 1 seta (rarely 2), 8— 10m in diameter A. repens 



Aphanochaete polychaete ( Hansg. ) Fritsch 1902, p. 410 



PL 17, Fig. 1 

 Sparsely branched, creeping on Cladophora filaments; composed 

 of rounded or oblong-rectangular cells, 9-15/i, in diameter, 1-2 times 

 longer than wide, with 2-6 (rarely only 1) setae arising from the 

 dorsal wall of each cell. 

 Rare. Wis. 



Aphanochaete repens A. Braun 1851, p. 196 

 PI. 17, Figs. 2, 3 



Filaments creeping on or entwined about larger filamentous algae. 

 Cells irregularly inflated or subcylindric, S-lO/x in diameter. Setae 

 long and very slender, S/x wide at the base. 



This is the most common of the species of this genus which occur 

 in North America. It is abundant in favorable habitats but seems to 

 be restricted in its distribution, occurring most frequently in shallow 

 warm water where there is a great mixture of algae. 



On many kinds of filamentous algae in shallow water of lakes 

 and swamps; intermingled with other algae. Common. Mich., Wis. 



Aphanochaete vermiculoides Wolle 1887, p. 119 



PI. 17, Fig. 4 



Filaments composed of short- or long-cylindric, or rounded cells, 



attached at 2 or 3 points only, on larger algae, highly arched and 



free between the points of contact. Setae sometimes absent, but 



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