68 Steele— Additions t<> the Plora of iVashington. 



gga. Polygala Curtissii A. Gray. 



Addison Heights. July 22, 1896, abundant. Also at Bennings and 

 Bladensburg. Perhaps our most common species. 

 ioo5. Polygala Nuttallii Torr. & Gray. 



Near Brightwood swamp. July 24. 1897; since collected on the liats 

 opposite Alexandria, and one mile north of Berwyn. It seems to prefer 

 the vicinity of swamps. 

 I02a. Polygala Senega latifolia Torr. & Gray. 



Common. Our plant, however, seldom has the leaves "2 inches long", 

 and some specimens growing with the others have the leaves nearly or 

 tjuite narrow enough for the type. 

 8oi. Phyllanthus Caroliiiensis Walt. 



This plant can no longer be regarded as rare. I have collected or ob- 

 served it on denuded banks in the up-river region, on the electric road 

 near St. Asaph's, on the gravelly flats, especially west of the road at 

 Jackson City (abundant), at a point on Riggs road near Northwest 

 Branch, and near Bladensburg. 

 *8oia. Crotonopsis linearis Michx. 



In a Hat moist Held perhaps three-quarters of a mile north of Berwyn, 

 July 28, 1900. 

 8o2a. Acalypha gracilens A. Gray. 



The smaller grayish leaves (often broader than would be expected 

 from the figure in Britton and Brown's Flora), and the slender outer 

 branches of the typical form separate this fairly from A. Virginica in 

 general appearance. The protrusion of the staminate flowers from the 

 involucre is not a reliable character, as some of the finest Virginica I 

 have seen has them well exserted. On feeble plants or branches the 

 involucre is sometimes almost obsolete. A low, stout form of this 

 species occurs on broken ground without the slender branches, and with 

 an abundance of small leaves and fruit. 

 *8oo«. Euphorbia dentata Michx. 



Sandy Held, Seven Locks, September 25, 1897; waste ground, river 

 front, very abundant in 1900. Common about Harper's Ferry. The 

 variation in the width of the leaf is cjuite extraordinary. 



798. Euphorbia Ipecacuanhae L. 



Sandy knoll, Hyattsville, east of creek. May 4, 1898: near Lutheran 

 Home, May 11, 1901. 



799. Euphorbia dictyosperma Fiscli. i\c Mey. 



Near Captain Jones' place beyond Chevy Chase Lake, and in great 

 abundance in a meadow opposite Forest Glen, May 17, 1900. 

 305a. Callitriche heterophylla Pursh. 



What I take-to be a form of this was collected in a warm pool at 

 Great Falls, May 30, 1899. The broad leaves are entirely absent. Nor- 

 mal form, Bladensburg, June 27, 1897. 



184. Rhus aromatica Ait. 



This i)lant is rather common around Harper's Ferry, and also in the 



