THE BOTANY OP THE ROUTE. 
Nasturtium palustre, DC. 
Nasturtium obtusum, Nutt. 
Nasturtium limosum, Nutt. 
Arabis hirsuta, Scop. 
Sisymbrium canescens, Nutt. A nearly glabrous variety. 
Erysimum cheiranthoides, Linn. 
Erysimum asperum, DC. 
Stanleya integrifolia, James. Without much doubt this is a mere state of S. pinnatijida. 
Stanleya pinnatifida, Nutt. 
Sinapis nigra, Linn. (Introduced.) 
Capsella bursa-pastoris, DC. 
Lepidium Yirginicum, Linn. 
Lepidium intermedium, Gray, PI. Wright. 
Draba micrantha, Nutt. 
Cleome integrifolia, Torr. & Gray. 
Viola cucullata, Ait. 
Viola palmata, Linn. 
Viola Canadensis, Linn. 
Elodea Virginica, Nutt. 
Mcehringia lateriflora, Penzl. 
Cerastium arvense, Linn. 
Cerastium mutans, Raf. 
Malvastrum coccineum, Gray. One hundred miles above Fort Pierre. 
Linum perenne, Linn. 
Linum rigidum, Pursh. 
Geranium maculatum, Linn. 
Oxalis violacea, Linn. 
O x a lts corniculata, Linn. 
Zanthoxylum Americanum, Mill. 
Rhus toxicodendron, Linn. 
Rhus aromatic a, Ait. White river, Nebraska. 
Ampelopsis quinquefolia, Michx. 
Ceanothus ovalis, Bigel., var. 
Staphylea trifolia, Linn. 
Negundo aceroides, Moench. 
Polygala alba, Nutt. 
Vicia Americana, Muhl. 
Lathyrus linearis, Nutt. 
Lathyrus polymorphus, Nutt. 
Lathyrus venosus, Muhl. 
Amphicarpa monoica, Ell. 
Glycirrhiza lepidota, Nutt. 
PSORALEA LANCEOLATA, Pursh. 
Psoralea argophylla, Pursh, and var. decumbens. Less silvery and silky-hirsute; stems 
slender, decumbent or diffuse; stipules mostly near equalling the short petiole; leaflets ellip- 
