500 



ONAGRACEAE. 



[Vol.. II. 



2. Circaea alpina L/. Smaller 



Enchanter's Nightshade. 



(Fig. 2611.) 



Circaea alpina L. Sp. PI. 9. 1753. 



Smaller, 3'-8' high, simple or branched, weak, 

 glabrate, or pubescent above. Leaves ovate, 

 slender-petioled, acute or acuminate at the 

 apex, more or less cordate at the base, coarsely 

 dentate, i'-2 r long; flowers about i" broad; 

 pedicels \ l /i"-i" long, reflexed in fruit; fruit 

 narrowly obovoid, about \" long, covered with 

 weak soft hooked hairs. 



In cold moist woods, Labrador to Alaska, south 

 to Georgia, Indiana, Michigan and Minnesota. 

 Also in Europe and Asia. Leaves thin, somewhat 

 shining. Ascends to 6300 ft in North Carolina. 

 July-Sept. 



1827. 



Family 88. TRAPACEAE Dumort, Fl. Belg. 90. 



\V.\TKR-NI-T FAMILY. 

 Aquatic herbs, with opposite pinnatifid submerged leaves, and clustered 

 rhombic-ovate dentate floating ones with inflated petioles. Flowers perfect, 

 axillary, solitary, short-peduncled. Calyx-tube short, the limb 4-parted, the 

 lobes persistent. Petals 4, sessile, inserted on the perigynous disk. Stamens 

 4, inserted with the petals; filaments subulate-filiform. Ovary 2-celled, conic 

 above; style subulate; ovule i in each cavity. Fruit coriaceous or bony, large, 

 2-4-spinose or swollen at the middle, i-celled, i-seeded, indehiscent. Seed in- 

 verted. 



A single genus of 3 species, natives of Europe, tropical Asia and Africa. 



i. TRAPA L. Sp. PI. 120. 1753. 



Characters of the family. [Latin, from Calcitrapa, the Caltrop.] 



i. Trapa natans L. Swimming 



Water-nut. Water-Chestnut. 



Water-Caltrop. (Fig. 2612.) 



Trapa natans L. Sp. PI. 120. 1753. 



Rooting in the mud at the bottom of lakes 

 or slow streams; stem often several feet long. 

 Submerged leaves approximate, pectinately 

 dissected, i'-4' long; floating leaves in a 

 rosette sometimes i broad, their blades 

 rhombic-ovate, sharply dentate above, broad- 

 ly cuneate and entire below, about i' wide, 

 glabrous and shining above, the conspicuous 

 veins of the lower surface beset with short 

 stiff hairs; petioles of the floating leaves 2'- 

 6' long, inflated and spongy; flowers white, 

 about 3" broad; fruit i'-2' long, armed with 

 4 somewhat recurved spines. 



Naturalized in ponds, eastern Massachusetts, 

 and near Schenectady, N. Y. Native of Europe. 

 Called also Sanghara-nut. Seed mealy, edible. 

 June-July. 



Family 89. HALORAGIDACEAE Kl. & Garcke, Bot. Erg. Wald. 151. 1852. 



WATER-MILFOIL FAMILY. 



Perennial or rarely annual herbs, mainly aquatic, with alternate or verticil- 

 late leaves, the submerged ones often pectinate-pinnatifid. Flowers perfect, or 

 monoecious, or dioecious, axillary, in interrupted spikes, solitary or clustered. 



