20 MICHIGAN ACADEMY OF SCIENCE. 



Silphium terebinthinaceum Jacq. Prairie Dock. 

 Tradescantia Virginica L. Common Spiderwort. 

 Utricularia resupinata B. D. Greene. Bladderwort. 



COMPARISON OF THE FLORA OF THE EASTERN AND THE WESTERN SIDES OF THE 

 STATE IN THE LATITUDE OF 4440'. 



On the east side, the latitude in question is near Harrisville in Alcona 

 county. On the west side it is near Frankfort in Benzie county. 



It has long been known that the climate -of the west shore where the 

 wind sweeps across Lake Michigan was milder in winter, and throughout 

 the year less variable than it is on the east side of the State. So far as 

 observed, the plants of the State which are only found in the vicinity of 

 the great lakes are more abundant in individuals on the west shore. 



A. NORTHERN PLANTS FOUND ON THE EAST SIDE OF THE STATE AND NOT ON THE WEST. 



Botrychium Lunaria (L.) Swartz. Moonwort. 



Botrychium simplex Hitchcock. Moonwort. 



Carex capillaris L. Sedge. 



Carex durifolia Bailey. Back's Sedge. 



(Carex Backii Boott.) 



Carex Houghtonii Torr. Sedge. 



Dracocephalum parviflorum Nutt. Dragon-head. 



Kalmia angustifolia L. Sheep Laurel. Lambkill. 



Kalmia glauca Ait. Swamp Laurel. Pale Laurel. 



Picea Canadensis (Mill) B. S. P. White Spruce. 



(Picea alia Link.) 



Ribes lacustre (Pers.) Poir. Swamp Gooseberry. 



Sparganium simplex Huds. 



B. SOUTHERN PLANTS FOUND ON THE WEST SIDE OF THE STATE AND NOT ON THE EAST. 



Adiantum pedatum L. Maiden Hair Fern v 

 Acer saccharinum L. Silver Maple. 

 (Acer dasycarpum Ehrh.) 

 Rubus occidentalis L. Black Raspberry. 

 Sambucus Canadensis L. Common Elder. 

 Sassafras Sassafras (L.) Karst. 

 (Sassafras officinale Nees.) 

 Ulmus fulva Michx. Red Elm. 

 Ulmus racemosa Thomas. Rock Elm. 



This list is doubtless incomplete, but so far as it goes it sustains the pre- 

 vailing notion that the west side of the State has the milder climate. We 

 might be able to see why silver maple, sassafras, black raspberry, red elm 

 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 bulbosa (L.) Oakes. 



(Calypso borealis Salisb.) 



Clintonia borealis (Ait.) Raf. 



Equisetum littorale Kuehl. 



Eriocaulon septangulare Withering. Pipewort. 



Gyrostachys stricta Rydb. Hooded Ladies' Tresses. 



(Gyrostachys Romanzffiana (Cham.) MacM.) 



Selaginella selaginoides (L.) Link. 



(Selaginella spinosa Beauv.) 



