86 ELATINACE^E. ( WATER- WORT FAMILY.) 



Var. gymnanthum (H. gymnanthum, Engdm. $ Gray), is a form, or per- 

 haps species, with strict stem and branches, or often unbranched, more clasping 

 heart-shaped stem-leaves, and a naked cyme, the floral leaves being reduced to 

 small awl-shaped bracts ; so that in aspect it approaches the next. Newcastle 

 Co., Delaware, Canby, and Illinois, E. Hall, thence southward. 



14. H. Canad^nse, L. Stem strict (6'-15' high), with the branches 

 erect ; leaves linear, 3-nerved at the base, obtuse ; cymes naked ; pods conical-oblong, 

 usually much longer than the calyx. Wet, sandy soil : common. June - Oct. 

 Flowers deep yellow, 2" - 3" broad when expanded. 



Var. major is a large form, l-2 high, with lanceolate leaves l' long, 

 3" wide, the upper acute. L. Superior, Bobbins; S. New York and southward. 



15. H. Drummbndii, Torr. & Gray. Stein and the mostly alternate 

 bushy branches rigid, erect (10'- 18' high) ; leaves linear-subulate, nearly erect, 

 1-nerved (3" -9" long); flowers scattered along the upper part of the leafy 

 branches, short-pedicelled ; pods ovoid, not longer than the calyx. (Sarothra Drum- 

 mondii, Grev. $ Hook.) W. Illinois and southward, in dry soil. 



16. H. Sardthra, Michx. (ORANGE-GRASS. PINE-WEED.) Stem and 

 bushy branches thread-like, wiry (4' - 9' high) ; leaves minute awl-shaped scales, 

 oppressed ; flowers minute, mostly sessile and scattered along the erect branches; 

 pods ovate-lanceolate, acute, much longer than the calyx. ( Sarothra gentianoides, 

 L. ) Sandy fields : common. June - Oct. 



3. EL ODES, Adans. MARSH ST. JOHN'S-WORT. 



Sepals 5, equal, erect. Petals 5, equal-sided, oblong, naked, imbricated in 

 the bud. Stamens 9 (rarely more), united in 3 sets; the sets separated by as 

 many large orange-colored glands. Pod 3-celled, oblong : styles distinct. 

 Perennial herbs, in marshes or shallow water, with small close clusters of flesh- 

 colored flowers in the axils of the leaves and at the summit of the stem. (Name 

 fXudrjs, growing in marshes, accidentally changed to ELODEA by Jussieu, who 

 was followed by Pursh, &c.) 



1 . E. Virginica, Nutt. Leaves closely sessile or clasping by a broad base, 

 oblong or ovate, very obtuse; filaments united below the middle. (Hypericum 

 Virginicum, L.) Common in swamps. July, Aug. 



2. E. petiolata, Pursh. Leaves tapering into a short petiole, oblong: fila- 

 ments united beyond the middle. From New Jersey south and westward. 



ORDER 17. EL.ATINACEJE. (WATER-WORT FAMILY.) 



Little marsh annuals, with membranaceous stipules between the opposite 

 dotlefts leaves, minute axillary flowers like Chickweeds, but the pod 2-5- 

 celled, and the seeds as in St. John's-wort. The principal genus is 



1. EL A TINE, L. WATER-WORT. 



Sepals 2-4, persistent. Petals 2-4, hypogynous. Stamens as many, rarely 

 twice as many, as the petals. Styles, or sessile capitate stigmas, 2-4. Pod 2 - 

 4-celled, several - many-seeded, 2-4-valved ; the partitions left attached to the 



