22 FLORA OF MICHIGAN. 



and rock elm thrive on the west shore and not on the east, but we are 

 unable to see why the northern plants found on the east shore should not 

 be found on the west shore. ; Perhaps there is some other reason than the 

 difference of climate of the present day. 



PLANTS SUPPOSED TO HAVE IMMIGRATED FROM THE NORTHEAST. 



Calypso borealis, Salisb. 



Clintonia borealis, Raf. 



Equisetum litorale, Kuhlewein. 



Eriocaulon septangulare, Withering. Pipewort. 



Selaginella spinosa, Beauv. 



Spiranthes Romanzoffiana, Cham. Ladies' Tresses. 



Trillium erectum, L. Wake Robin. 



Trillium erythrocarpum, Michx. Painted Trillium. 



PLANTS SUPPOSED TO HAVE IMMIGRATED FROM THE NORTH AND WEST. 



Adenocaulon bieolor, Hook. 

 Anemone parvifl ora, Michx. Anemone. 

 Artemisia Ludoviciana, Nutt. Mugwort. 

 Bromus breviaristatus, Thurber. Brome Grass. 

 Castilleia pallida, Kunth., var. septentrionalis, Gray. Painted Cup. 

 Drosera linearis, Goldie. Sundew. 

 Echinacea angustifolia, DC. Purple Cone-flower. 

 Euphorbia serpyllifolia, Pers. Spurge. 

 Olyceria pallida, Trin. 

 , Iva xanthiifolia, Nutt. Marsh Elder. 



Lonicera involucrata, Banks. Honeysuckle. 



Mertensia paniculata, Don. Lungwort. 



Mimulus Jamesii, Torr. Monkey-flower. 



Mimulus moschatus, Dougl. Monkey-flower. 



Nasturtium obtusum, Nutt. 



Parnassia palustris, L. Grass of Parnassus. 



Parnassia parviflora, DC. Grass of Parnassus. 



Phacelia Franklinii, Gray. 



Polyonum lapathifolium, L., var. incanum, Koch. Knot weed. 



Potentilla frigida, Vill. Cinque-foil. 



Pyrus sambucifolia, Cham. & Schlecht. Mountain Ash. 



Ranunculus Ffammula, L., var. intermedius, Hook. Spearwort. 



Rosa acicularis, Lindley. Rose. 



Rosa Eugelmanni, Watson. Rose. 



Rosa Sayi, Schwein. Rose. 



Rumex salicifolius, Weinmann. White Dock. 



Symphoricarpos occidentalism Hook. Snowberry. 



' 



OVERLAPPING OF NORTHERN AND SOUTHERN SPECIES IN THE GRAND RIVER 



VALLEY. 

 NORTHERN SPECIES: 



Carex Magellanica, Lam. Sedge. 



Oarex pauciflora, Lightf. Sedge. 



Carex tenuiflora, Wahl. Sedge. 



Dracocephalum parviflorum, Nutt. Dragon-head. 



Eriophorum vaginatum, L. Cotton-grass. 



Lonicera oblongifolia, Muhl. Swamp Ply-Honeysuckle. 



Mimulus Jamesii, Torr. Monkey-flower. 



Primula Mistassinica, Michx. Primrose. 



Symphoricarpos racemosus, Michx., var. pauciflorus^ Robbins. Snowberry. 



Taxas Canadensis, Willd. American Yew. Ground Hemlock. 



SOUTHERN SPECIES: 



Asimina triloba, Dunal. Papaw. 



Carya sulcata, Nutt. Big Shell-bark. King-nut. 



Cassia Marilandica, L. Wild Senna. 



