134 Trans. Acad. Set. of St. Louis. 



sist through the winter and send out new branches in the 

 spring; such are Lycopus sinuatus, Lippia lanceolata and 

 Dianthera Americana. 



Propagation by Adventitious Buds upon Creeping Roots. 

 Creeping roots of the typical form are produced by Rhus 

 glabra, Ambrosia psilostachya, Cnicus undulatus, Apocynum 

 cannabinum, Enslenia albida. Convolvulus arvetisis, and 

 Rumex Acetosella, some of which are, on this account, bad 

 weeds. Asclepias Cornuti has a thick oblique root producing 

 buds along its surface. Sometimes the new plants thus pro- 

 duced form a crown as in Ascelepias vertic'llata . 



Solanum Carolinense and several species of Physalis have 

 a very deep slender vertical or horizontal root. Shoots may 

 start from this at considerable depth, and may become slender 

 crowns, thus giving the impression that the plant propagates 

 bv rhizomes. 



As to the relation between underground parts of plants and 

 their habitatlittle can be said. On the stony hills, crownformers 

 are the rule. Species with rhizomes ( Comandra pallida) and 

 creeping roots (Rhus glabra) are rare. Even in these cases 

 crowns are also formed. Rhizomes are not produced on prairie 

 species to any great extent but rather on our mesophyte 

 species inhabiting the rich loam of our woods or moist places 

 along streams and sloughs. All kinds are found about equally 

 in the sand-hills. Of course the perennial weeds of culti- 

 vated soil are those producing rhizomes or creeping roots 

 rather than the crown formers. 



Clematis Pilcheri, Torr. & Gray. A woody vertical crown 

 several inches long covered with fibrous roots. Moist thickets. 



Anemone decapetala, L. Vegetative stems arise from small 

 tubers. After flowering, the tubers send out slender white 

 rhizomes which form tubers at the apex. These tubers pro- 

 duce the vegetative stems of the following spring. Prairie. 



Anemone Virginiana y L. A slowly creeping oblique rhi- 

 zome. Open woods. 



Thalicirum purpurascens, L. A slowly creeping rhizome, 

 only one-half to one inch long. A strong bud is produced 

 just beyond the base of the vegetative stem. Low prairie or 

 open woods. 



