120 



AGRICULTURAL COLLEGE. 



[No. 17. 



SALICACK-K. 



Willow. 



Aspen. 



Downy Poplar. 

 Cotton- wood. 



Angled Cotton- 

 wood. 



Salix 



many species, but not yet fully 



identified. 



Red Cedar. 



Indian Turnip. 

 Green Dragon. 

 Calamus. 



Duckweed. 



Cat-tail Flag. 



Populus tremuloides, Michx. 



Ames ; Charles City ; BurliDgton. 



Populus heteropliylla, L. 



Fayette. 



Populus monilifera, Ait. 



Ames ; Fayette ; Burlington. 



Populus angulata, Ait. 



Ames. 



CONIFERS. 



Several Pines and Firs grow in the northern portions of the 

 State, but I have been unable as yet to secure reliable in- 

 formation regarding them. 



Juniperus Yirginiana, L. 



On Rocky bluffs of Des Moines river, Boone county, and in the 

 eastern part of the State along Cedar River ; Burlington. 



ARACE^:. 



Arissema triphyllum, Torr. 



Ames ; Indianola ; Grinnell ; Charles City ; Fayette ; Burlington. 



Arissema Dracontium, Schott. 



Ames. 



Acorus Calamus, L. 



Hamilton county. 



LEMNACE.E 



Lemna minor, L. 



Ames. 



Lemna polyrrhiza, L. 



Ames. 



TYPHACE^E. 



Typlia latifolia, L. 



Ames ; Burlington. 



