226 CONTRIBUTIONS FROM THE NATIONAL HERBARIUM. 



1. Lysimachia nummularia L. Moneywort. 

 Moitft places, chiefly in alluvial soil; well established at several localities. May- 

 June. Naturalized from Eur. in the northeastern U. S. 



2. Lysimachia quadrifolia L. Crosswort. 

 Moist or dry open woods, or low meadows or thickets; common. May-June. 



Eastern N. Amer. 



3. Lysimacliia terrestris (L.) B. S. P. 



Low moist or marshy situations; not uncommon, especially along the Potomac. 

 June- July. Eastern N. Amer. {L. stricta Ait.) 



Lysimachia producta (A. Gray) Fernald, a supposed fertile hybrid of the two last 

 pecies, is intermediate in characters. It is known locally from two collections. 



3. STEIRONEMA Raf. Loosestrife. 



Stem leaves narrowly linear, stiff, prominently 1-nerved, the lateral veins obscure. 



1. S. quadriflorum. 

 Stem leaves narrowly lanceolate to ovate or oblong, thin, pinnately veined. 

 Upper leaves with broadly lanceolate to ovate blades; petioles long, copiously long- 



ciliate throughout 2. S. eiliatum. 



Upper leaves with narrowly lanceolate to oblong blades; petioles often not sharply 

 separated from the blades. 

 Basal leaves and lower stem leaves mostly persistent, the blades round to oblong 

 or oval; stem usually simple; petioles ciliate throughout, the hairs extending 

 along the basal part of the blade; pedicels mostly shorter than the leaves. 



3. S. hybridum. 



Basal leaves and lower stem leaves reduced or rarely persistent; stem commonly 



branched; petioles ciliate chiefly at or near the base; pedicels usually longer 



than the leaves 4. S. lanceolatum. 



1. Steironema quadriflorum (Sims) Hitchc. 



Moist open places; two or three stations on the Potomac Flats near Chain Bridge; 

 apparently rare. June-Aug. Northeastern U. S. {S. longifolium A. Gray.) 



2. Steironema eiliatum (L.) Raf. Fringed loosestrife. 

 Low moist thickets, chiefly along the Potomac; common. June-July. Widely dis- 

 tributed in N. Amer. 



3. Steironema hybridum (Michx.) Raf. 



Around pools; locally common at Great Falls (both sides of the River) and above 

 Sandy Landing, but not found elsewhere. June-July. Eastern U. S., west to Ariz. 

 (S. eiliatum hybridum A. Gray.) 



Closely related to <S. lanceolatum but, on the basis of local specimens, distinct. 



4. Steironema lanceolatum (Walt.) A. Gray. 



Low or marshy situations; half a dozen localities, mostly along the lower Potomac; 

 apparently not uncommon. June-Aug. Eastern U. S. 



4. ANA6ALLIS L. Pimpernel. 



1. Anagallis arvensis L. Poor man's weather-glass. 



Pastures and waste places; several scattered localities. July-Sept. N. Amer. 

 generally; naturalized from Eur. 



6. CENTUNCULUS L. 



1. Centunculus minimus L. Chaffweed. 



Moist soil; uncommon; Woodlawn, and region of Hyattsville and Bladensburg. 

 June. Eastern U. S. and westward. 



