PLANTS OF IOWA 



979. 0. tenuis, Ag. 



This is the most common of the Oscillarias, b* ing almoei 

 universally present in stagnant water, and in 

 running streams, where water drops upon the bo I. on 

 boards, etc., or stone under a water drop, \< r. 

 mat. 



980. 0. limosa, Vauch. 



Next to the Tenuis this is probably the coma 

 species in the state. On damp earth, forming a thin 



coating. Moist earth. 



981. 0. nigra, Vauch. 



Usually floating free in stagnant water. In stagnant 

 ditch. 



982. 0. froelichii, Kuetz. 



Floating among other alga? in ponds. 



983. 0. froelichii, var. fusca, Kirch. 

 On moist soil in the greenhouse. 



984. 0. princeps, Vauch. 



Pond, amid dense growth of Lemna. 



985. 0. imperator, Wood. 



The largest species of Osc Maria that is to be found in 

 the state. 

 Microcoleus, (Desm.) Thur. 



986. M. vaginatus, (Vauch.) Comont. (M. terrestris, Eg.) 

 Damp ground. On flower pots in greenhouses. 



Phormidium. 



987. P. tenue, (Menegh.) Gomont. 



On pots in greenhouse. Pond. In pond among de 

 ing rushes. 

 Lynbya, (Ag.) Thur. 



988. L. vulgaris, (Kuetz.) Kirch. 

 Damp soil. 



989. L. ochracea, (Kuetz.) Thur. 



In the trough of a flowing well. It is found wry com- 

 monly in the water in this locality thai are laden with 

 iron, the sheath becoming impregnated with this sub- 

 stance. 



