PAPERS BY MEMBERS 87 



Microthamnion strictissimum Rabenhorst. 



Not infrequent in streams during the cooler months of 

 the year. 

 Chaetosphaeridium globosum ( Xordstedt) Klebahn. 



Rather common in temporary ponds on submerged seed 

 plants. Early spring. 

 Chaetophora elegans (Roth) Agardh. 



A very common alga in ponds and streams, attaining 

 its largest size and greatest abundance in the prairie 

 ponds, during April and May. 

 Chaetophora incrassata ( Huds.) Hazen. 



Very common in pools, ponds and streams. Our largest 

 specimens are less than eight centimeters in length. 

 Usually associated with species of Draparnaldia. 

 Chaetophora pisiformis (Roth) Agardh. 



The only collection containing material that could satis- 

 factorilv be placed here came from the Tile Factory 

 pond. Arthur. May. 1912. 

 Stigeoclonium glomeratum (Hazen) Collins. 



Rather common in ponds and pools during March and 

 April. 

 Stigeoclonium lubricum varians (Hazen) Collins. 



Our most abundant species of Stigeoclonium. Usually 

 found in intermittent streams during the period from 

 November to April. Also occurs in ponds, pools and 

 ditches. 

 Stigeoclonium nanimi ( Dilhv.) Kuetzing. 



Recorded from Cut-off of Polecat creek near Ash- 

 more. April, 1912. 

 Stigeoclonium stagnatile (Hazen) Collins. 



Common in ditches and pools in early spring on the 

 prairie. 

 Stigeocloniimi tenue ( Ag.) Kuetzing. 



Rare in temporary ponds and pools, particularly the 

 remnants of old prairie ponds. 

 Draparnaldia acuta (Ag.) Kuetzing. 



Rare. Specimens that seemed best classified here have 

 been collected from the east branch of Campus creek, 

 and a small stream on the D. B. ^liller farm southwest 

 of Casey. 

 Draparaldia glomerata i \*auch.) Agardh. 



Rare. Only recorded from a drainage ditch north of 

 Paris. 

 Draparnaldia plumosa ( Vauch.) Agardh. 



This is the commonest species of the genus. It is very 

 abundant in the streams particularly of the forested 

 soils. It is common in the ponds both of the forested 



