194 American Midland Naturalist Monograph No. 7 



4. Leaves elliptical-lanceolate, entire or nearly so; flowers 



yellow with a brownish center; fruiting calyx green, 3- 

 3.5 cm long; an occasional railroad migrant from the 



western states. July-Sept P. longifolia Nutt. 



3. Pedicels pubescent. 



5. Pedicels strigillose to hispidulous, the hairs pointing for- 



ward; fruiting calyx scarcely sunken at the base. 



6. Pedicels antrorsely strigillose; stem and leaves nearly 



glabrous, the latter ovate-lanceolate; anthers 3 mm 



long, shorter than the strongly flattened filaments; 



roadsides and cult, ground, common. June-Sept. 



Smooth Ground-cheny P. subglahrata Mack. & Bush 



6. Pedicels antrorsely hispidulous; stem and leaves short- 

 hirtellous, the latter elliptical-lanceolate; anthers 2 

 mm long, longer than the filaments; diy ground, occa- 

 sional; adv. from western U.S. May- July 



P. lanceolata Michx. 



5. Pedicels retro rsely or spreading-hispidulous; anthers 2 mm 

 long, not longer than the slender filaments; fruiting calyx 

 pyramidal-ovoid, obtusely 5-angled, deeply impressed at 

 the base; roadsides and cult, ground, common. May- 

 July. [P. lanceolata of auth., not Michx.]. Virginia 



Ground-cherry P. virginiana Mill. 



2. Plants annual with fibrous roots, easily pulled out of the ground. 

 7. Pedicels much shorter than the flowers, puberulent or gla- 

 brous; calyx-lobes deltoid-ovate; corolla with a brownish- 

 purple center; waste places and cultivated ground, occa- 

 sional; native of Mexico and southwestern U.S. Tomatillo 



P. ixocarpa Brot. 



7. Pedicels longer than the flowers; corolla wholly yellow; calyx- 

 ,. lobes lanceolate. 



8. Pedicels much longer than the fruiting calyx; corolla 5-8 



mm broad; alluvial soil, occasional. July-Sept 



P. pendula Rydb. 



8. Pedicels scarcely longer than the fruiting calyx; corolla 8- 



10 mm broad; waste places, occasional P. angulata L. 



1. Stem and leaves more or less glandular-pubescent or villous; 

 pedicels spreading-pubescent. 

 9. Plants perennial with a rhizome. 



10. Pubescence of forked hairs; leaves elliptical, entire or some- 

 what sinuate, tapering at the oblique base; waste ground, 

 roadsides, along railroads, occasional ; native west of the 

 Mississippi R. Cook Co., Pepoon; Peoria, V. H. Chase 



in 1921 P. pumila Nutt. 



10. Pubescence of simple hairs; leaves ovate, rounded to oblique- 

 ly subcordate at base, sinuate, copiously grayish vil- 

 losulous, the pubescence usually glandular and viscid; 

 sandy or alluvial soil, in fields and open woods, or in waste 



