240 ONAGRACE^. Circ^a. 



2. CiRC^A ALPiNA, Linn. Alpine Enchanter's Nightshade. 



Stem weak ; leaves cordate, shining, rather coarsely toothed, the lower ones as long as the 

 petioles ; pedicels with a minute setaceous bract at the base ; disk scarcely projecting beyond 

 the tube of the calyx. — Linn. sp. I. p. 8; Engl. hot. t. 1057 ; Michx. fl.\. p. M ; Piirsh, 

 fi. \.p.2\; Torr.fi. !.;>. 30; Bigel. fl. Bost. p.U; Hook.Jl. Bor.-Am. 1. p. 215; Torr. 

 4- Of. fl. N. Am. 1. p. 527. 



Stem 4-8 inches high, sometimes assurgent. Leaves very thin and somewhat translucent, 

 broadly cordate, always either cordate or truncate at the base ; the lower ones with elongated 

 petioles. Flowers and fruit as in the preceding species, but considerabl}' smaller ; the hairs 

 on the fruit also are weaker. 



Dense woods, on prostrate trunks of trees, and about springs, particularly in mountainous 

 districts ; very common in the northern and western parts of the State ; not foimd south of 

 Catskill. July - August. The two species of Circ(ta are verj' nearly allied, but they can 

 usually be distinguished by the characters here given. Some botanists consider them varieties 

 of one species. 



Suborder HALORAGEiE. R. Br. ; DC. (excl. Callitriche). 



Limb of the calyx 3 - 4-lobed or -toothed, sometimes nearly wanting. Petals 

 3 — 4, or wanting. Stamens double the number of the petals, or equal to them, 

 or fewer, inserted with the petals into the throat of the calyx. Ovary cohering 

 with the calyx, 1 - 4-celled : style none : stigmas equal in number to the cells, 

 papillose or pencil-formed. Fruit 1 - 4-celled, membranaceous or bony, in- 

 dehiscent, with a solitary pendulous seed in each cell. Embryo straight, in 

 the centre of thin fleshy albumen : radicle long and slender : cotyledons smalL 

 — Herbaceous or somewhat shrubby plants, gromng in wet places or in water. 

 Leaves alternate, opposite or verticillate. Flowers very small, axillary, sessile, 

 or in spikes, sometimes monoecious or dioecious. 



6. PROSERPINACA. Linn. ; Juss. in ann. mus. 3. p. 320. t. 30./. 1 ; Endl. gen. 6137. 



MERMAID- WEED. 

 [ From the Latin, proscrpo, to creep ; the stems creeping and rooting at the base.] 



Tube of the calyx 3-sided ; the limb 3-parted. Petals none. Stamens 3. Stigma oblong, 

 papillose. Fruit bony, triangular, 3-celled. — Perennial aquatic herbs ; the stems creeping 

 at the base. Leaves serrate or pectinately cut. Flowers axillary, perfect, solitary or 

 several togeilier. 



