30 DIANDRIA. MONOGYNIA. circma, 



inserted at the base of the petals, and equalling; them in length; 

 anthers round. Style filiform ; stigrna capitate. Fruit covered 

 with minute hooks, reflected with the footstalks when old. 

 Seeds oblong. 

 Hab. In shady moist woods ; common. July — August. 



2. C. alpinn L. : stem branched, very smooth, often 

 procumbent ; leaves broad-cordate, membranaceous, acutely 

 toothed, shining. Mich. FL I. p. 17. Willd. Spec. I, 

 p. 53. Vahl Enum. I. p. 301. Pursh FL I. p. 21. 

 Eng.Bot. t. 1057. Roem. <^ Schult. 1. p. 271. 



Eooe perennial. Stem 6 — 8 inches high, swelling at the joints, 

 and somewhat diaphanous. Leaves on long petioles, spread- 

 ing horizofitally, very bioad in proportion to their length, of a 

 thin and delicate texture; teeth distinct and somewhat unci- 

 nate. Raceme filiform, branched below. Calyx membrana- 

 ceous. Petals reddish white, narrowed at the base. Fruil 

 pubescent, but not hispid. 



Hab. On rotten prostrate trees, and on mossy rocks, in wet 

 shady woods. Seldom found south of 42° N. latitude. Com- 

 mon in the northern parts of the State of ISew-York. August, 



23. LEMNA. L. 



Calyx 1 -leaved, entire. Corolla o. Fruit a utricle. 

 (Seed 1, l\ing horizontally, and affixed by its lower 

 side.) Hook. FL ScoL I. p. 10. Gefi. pL 1400, 

 Nutt. G'<?;?. I. p. 18. Roem.'i^ Schult. Gen.lll^ 

 Lam. IlL t. DCCXLVII. Lenticula MichelL 

 Jiiss.\>.\^. Nat. Ord. Naiades* /z^ 5 J. Aqua- 

 tics, floating on the surface. Fronds (Hooker; 

 leaves Lin. Sec.) increasing laterally; roots calyp- 

 trated at their extremities. M o n o e c i a Diandria L i n, 



Duckh-meat. 



1. L. trisuica L. : fronds thin, elliptico-lanceolate, cau- 

 date at one extremity, at the other serrate; roots solitary. 

 Hook. FL Scot. I. p. 10. fViUd. Spec. IV. p. 193, 

 MuhL Cat. p. 86. Eng. Bot. t. 926. Rotm. <^ Schult. 

 I. p. 282. 



jinnual, as are all of the genus, (fierennial Mu h I. l ) Fronda 

 about 3-f.)urth3 of an inch long, pellucid, flat, smooth : on each 

 side of the margin is a cleft, from which a young plant is pro- 



• R Bvo-un proposes to place the genus Lemna, together with Char a 

 and Najas, among the HiDaocHABiDEAE. •• A Jussieu inter Fiiicis tf\\- 

 turn." R. a S. 



