HOFFMANN: FLORA OF BERKSHIRE COUNTY. 289 



APIOS. Gkound-nut. 

 {Glycine lU. Fl. ed. 2.) 



A. tuberosa Moench. Gbound-nut. — (G. Apios 111. Fl. ed. 2.) 

 Alluvial thickets and rich damp upland; frequent in the valley. 



BAPTISIA. False Indigo. 



B. tinctoria (L.) R. Br. Wild Indigo. — Sandy soil in open 

 woods; common in the southern part of the valley. 



CASSIA. Senna. 



C. marilandica L. Wild Senna. — Roadsides in low ground; 

 occasional in the southern part of the valley. West Stockbridge; 

 Egremont; SheiBeld. 



CORONILLA. 



C. VAEiA L. — Occasionally established along roadside banks in the 

 valley. 



CROTALARIA. Rattle-box. 



C. sagittalis L. Rattle,-box. — Sand-plain, Sheffield. 



DESMODIUM. Tick Tbefoil. 

 {Meihomia 111. Fl. ed. 2.) 



Key to Desmodium. 



1 . Plant prostrate D. rotundifoUum. 



S. Plant erect. 



a. Pod raised on a, stalk many times longer than the slightly toothed 

 calyx. 

 Leaves all crowded at the summit of sterile stems . . . .D. nudiflorum. 

 Leaves all crowded at the summit of the stem from which arises the 



elongated panicle D. grandiflorum. 



a'. Pod raised on a stalk little it at all surpassing the deeply cleft calyx. 

 b. Stipules conspicuous and persistent; flowers rather large; stem 



smooth D. bracieosum. 



b'. Stipules mostly deciduous, small and inconspicuous, 

 c. Flowers middle-sized, not very showy. 



Stem pubescent; leaflets softly and finely pubescent. 



D. Dillenii. 



Stem smooth; leaflets smooth D. paniculaium. 



c'. Flowers 8 to 12 mm. long, showy; stem hairy. . . .D. canadense. 



