306 Hill: Notes ox Plants of the Chicago District 



the sand hills and rid^^cs of Tolleston, Ind.; and Aristida gracilis 



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Ell., from Pine near the lake shore. The latter grows in ground 



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that can hardly be called dry, for it occurs In sand bordering • 

 sloughs dry at the time of fl-oweriiig. Yet one can reach out and 



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get Utricularia cornnta and U. gibha with one hand while taking 

 the Aristida with the other, so that its spring or early summer con- 

 dition must be quite moist or even wet. Panicum ficxilc and P. 

 pubcscens arc grasses commonly growing with it showing the com-- 



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posite ecological character of the soil conditions often seen in the. 

 dune flora, baffling one sometimes to determine whether they are. 

 xerophytic or hydrophytic, since they are both at different times 

 of the year. The wettish sands of the spring and early summer 

 provide the seeds of these annual grasses with better means of 

 germination than the drier ridges subject, to the wind and where. 

 the vegetation is scantier, the ground more bare, so that they grow 

 more abundantly and luxuriantly in ground that becomes dry and 

 suits a xerophytic plant when near its maturity. The westward 



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distribution of Vitis Labnisca, which was obtained in the dune re- 

 gion in 1897, Was discussed at large in an article in the Bulletin 

 of the Torrey Botanical Club in October, 1897. 



Among the drift hills near Mokena, south of Chicago, two 

 Ccirices occur which have a southern range for this meridian, C. 

 Shortiana Dewey, in wet meadows, and C, triceps Michx. in oak 

 woods. The latter has a single station given it farther north in 

 the central part of southern Michigan, and both range in Illinois 

 from Peoria south. Cypcnis acuniinafusTovr. and Hook., a sedge 

 with a southwestward extension, was found last year by the Des- 

 plaines River at Lockport, 111. It has been known hitherto in the 

 state as a plant of the valley of the Illinois River and towards the 



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Mississippi. The three are still plants of the Illinois valley for 



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our region as they are beyond the divide which separates the lake. 

 region from streams flowing toward the Mississippi... 



Some plants with a general, northern range or adapted to colder 

 conditions have been added to our flora., Carex oligospcrma 

 Michx. comes into the dune rec^ion from the north, being found 



in sphagnous swamps and in cranberry marshes at Miller, Ind; 

 The little bitter cress, Cardaniinc parviflora L., was obtained in 

 tlie oak woods with Carcx triceps though I have, occasionally met 



