IOWA ACADEMY OF SCIENCES. 173 



MARCHANTIACE^. 



Marchantia polymorpha L. Johnson Co. Low grounds and 

 over rocks, common. 



Gonocephalus conicus Dumort. Johnson Co. Rocks along 

 shallow streams, common. 



Asterella hemispherica Beauv. Johnson Co. On shady moist 

 banks, common. 



RICCIACE^. 



Riccia crystallina L. Decatur and Johnson Cos. Fields and 

 mud flats, common. 



R. fluitans L. Johnson Co. Cratty sends us the same from 

 Emmet Co. Floating on water, perhaps not common. 



13 [la. Acad. Sci.. Vol. v.| [July 5, 1898. 1 



