EXOGENOUS PLANT S. 



609 



cuius fascioularis, (Mulil.) April. Dry river banks. Ranunculus rcpens, (L.) May. Wet places, com- 

 mon. Caltlia palustris, (L.) May. Swamps. Coptis trifolia, (Salisb.) Bogs. St. Croix. Isopyrum 

 biternatum, (Torr and Gr.) Shady woods, Blue Earth River. Aquilegia Canadensis, (L.) June. Rocks. 

 Delphinium azureum, (Michx.) June. A characteristic Larkspur, growing on sandy ridges or high 

 prairies, Iowa and Illinois. Actrca rubra, (Willd.) May. Woods and Copses, Iowa. Acttea alba, 

 (Bigel.) With the preceding. 



ANONACEiE. — Asimina triloba, (Duval.) April. " Papaw." Head of Des Moines Rapids, Missis- 

 sippi River. 



Menispermace/e. — Menispermum Canadense, (L.) May. A common vine. The root is a popular 

 tonic. 



Berberidace^e. — Leontice thalictroides, (L.) April. Woods. Podophyllum peltatum, (L.) May. 

 Rich woods, the fruit eatable ; the root cathartic. 



CABOMBACEiE. — Brasenia peltata, (Pursh.) July. " Water shield." Floating on shallow lakes, St. Croix. 



NYMPHiEACEiE. — Nymphrca odorata, (Ait.) July. Water lily. Nuphar advena, (Ait.) July. 

 Yellow water lily. 



Sarraceniace/e. — Sarracenia purpurea, (L.) June. Pitcher plant. Bogs of the St. Croix. 



Papaverace^e. — Sanguinaria Canadensis, (Linn.) April. The medicinal blood root. 



FuMARlACEiE. — Dicentra Cucullaria, (D. C.) April. Rich woods. Corydalis aurea, (Willd.) May. 

 River banks. A very variable plant, according to the character of the soil in which it grows. Cory- 

 dalis glauca, (Pursh.) August. Trap rocks, at Falls of St. Croix. 



CRUCiFERiE. — Nasturtium sinuatum, (Nutt.) July 14th. River bank, Lower St. Peter's. Found 

 also in similar situations in Oregon. Nasturtium palustre, (D. C.) July. River banks. Nasturtium 

 natans, (D. C.) July. A singular aquatic species, more common in the West than at the East. Car- 

 damino rhomboidea, (D. C.) May. Wet places in prairies, Iowa. Cardamine hirsuta, (L.) May. 

 Moist margins of brooks. Dentaria laciniata, (Muhl.) April. Rich woods. Arabis lyrata, (L.) May. 

 Rocks. Galena, 111. Arabis dentata, (Torr. and Gr.) June. River banks. Arabis hirsuta, (Scop.) 

 May. Rocky places, head of Lake St. Croix. Arabis ltevigata, ! (D. C.) May. Rocky river-banks. 

 Arabis Canadensis, (L.) June. St. Peter's and St. Croix. Erysimum cheiranthoides, (L.) July. 

 River banks. Sisymbrium canescens, (Nutt.) May. Pastures and river-banks, Davenport, Iowa. 

 Draba Caroliniana, (Walt.) April. Dry and exposed banks of the Mississippi, Davenport, and Rock 

 Island. Lcpidium Virginicum, (L.) Waste places. Capsella bursa-pastoris, (Moanch.) Fields and 

 streets. 



CapparidacevE. — Polanisia graveolens, (Raf.) July. Gravelly banks of the Upper Mississippi. 



Vxolace/e. — Viola cucullata, (Ait.) April. Low grounds. Viola pedata, (L.) May. A showy 

 species, adorning the rolling prairies of Iowa with its early blue blossoms. Viola delphinifolia, 

 (Nutt.) May. Davenport and Upper Mississippi. Closely resembling the former, but readily distin- 

 guished on a close examination. Viola Canadensis, (L.) June. St. Peter's. Viola Muhlenbergii, (Torr.) 

 May. Lake St. Croix. 



Cistace^i. — Heliantbemum Canadense, (Michx.) June. Dry hills and prairies. Iowa and Minne- 

 sota. Hudsonia ericoides, (L.) Common to the shores of Lake Superior, the barren ridges of the St. 

 Croix, and the Atlantic sea-beach. Lechea minor, (Lam.) July. " Pin-wee." St. Croix. 



DroseracevE. — Drosera rotundifolia, (L.) July. "Sun-dew." Moist sand on the margins of lakes. 

 Minnesota. Parnassia Caroliniana, (Michx.) August. Wet places on prairies. St. Peter's and St. 

 Croix. 



HypericacevE. — Hypericum pyramidatum, (Ait.) July. River banks Upper Mississippi and St. 

 Peter's. Hypericum Canadense, (L.) August. St. Croix River. Elodea Virginica, (Nutt.) July. 

 Swamps in the Northwest. 



Caryophyllace/E.— -Silene stellata, (Ait.) July. Woods and river banks. Silene nivea, (D. C.) 

 July. Ravines. Davenport, Iowa. Silene antirrhina, (L.) June. Dry soil and exposed rocks. Iowa 

 and Minnesota. Arenaria stricta, (Michx.) July. Rooting on detached rocks, head of Lake St. Croix. 

 Moehringia lateriflora, (Feuzl.) May. Wet places, St. Croix. Stellaria longifolia, (Muhl.) May. 

 Moist, grassy places, Upper Mississippi. Cerastium nutans, (Raf.) May. Moist, sandy places, Upper 

 Mississippi. Mollugo verticillata, (L.) August. Exposed rocks and sandy fields, St. Croix. 



PoRTULACACEiE. — Portulaca oleracea, (L.) Crevices of rocks on the Upper St. Peter's. Talinum 



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