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The shale-slope plant has a compact habit, with the internodes about 

 equalling the petioles ; the pubescence dense and velvety ; the leaf- 

 blades lanceolate to oblong, conspicuously auriculate with but 

 slightly divergent lobes 5-10 mm. long, and persistently condupH- 

 cate; the petioles 10-15 mm. long, about 1-3 the length of the 

 blades ; and the bracts ovate, often nearly as broad as long, more 

 or less cordate, and rather strongly keeled. 



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Convolvulus stans Michaux, on calcareous shale just north of Flintstone, 

 Allegany County, Alaryland, May 30, 1928. Edgar T. Wherry, photo. 



Unlike the Longleaf Clover, this Convolvulus is not limited to 

 Appalachian shale-slopes, but occurs occasionally on gravel derived 

 from other types of rock, and extends a considerable distance 

 northward, even entering southern Canada. It was apparently 

 first recognized in the latter region by Michaux,* and named Con- 

 volvulus stans. Pursh'^ renamed it Calystegia pubescens, and 



* Fl. Bor. Amer. 1: 136. 1803. 

 Tl. Amer. Sept. 1: 143. 1814. 



