POLYANDRIA POLYGYNIA 327 



bn* adnate anthers. Ovaries closely imbricated; stigmas sessile, recurved. 

 Calvcls 2-celled, samara-like, with a lance-oblong wing at apex, incurved at base, 

 with a prominent internal ridge, imbricated in a cone, upon a slender fusiform 

 receptacle,-one of the cells frequently obliterated, and both seeds often abortive. 

 Hub. Rich woodlands: common. Fl May. Fr. October. 



Obs The tcoal of this magnificent tree is highly valued in the mechanic arts, 

 especially the variety called yellow poplar ;- which is generally to be known by 

 its thicker and more deeply furrowed bark. The bark is also a valuable aromatic 

 bitter ; and has been successfully used in intermittents. It is the only species in 

 the l\ States-if not the only one of the genus. 



260. RANUNCULUS. L. Nutt. Gen. 49 1 . 

 [Latin, Rana, a frog ; the plant often growing where frogs abound.] 



Calyx of 5 deciduous sepals, not produced at base. Petals 5 (some- 

 times 10), each with a nectariferous scale, or pore, at base on the inside. 

 Carpels somewhat compressed, ovate, mucronate, striate, smooth, or tu- 

 berculatc, arranged in a globose or cylindric head. 



Herbaceous: mostly acrid j leaves alternate, entire, dentate, or multifid : ped un- 

 ci s terminal, axillary, or opposite the leaves. Nat. Ord. 3. Lindl. Kamncu- 



LACS22. 



f Carpels tratisversely rugose-striate. 

 1. R. AarATiLis, L. var. capillaceus, J)C. Stem filiform, floating; 

 leaves all submersed, divided into capillaceous segments ; petals obovate- 

 oblong, longer than the calyx. Beck, But. p. 7. 

 R. fluviatilis. mild. Sp. 2. p. 1333. Pers. Sim. 2, p. 106. l>uvsh, 

 Am. 2. p. 395. Nutt. Gen. 2. p. 23. Bart. Phil. 2. p. 26. Bigel. Bost. 

 p. 227. Florul Cestr.p. 61. Eat. Man. p. 297. 

 R. pantothrix. Ell. Sh. 2. p. 56. Lindl ? Ency. p. 488. 



Water Ranunculus. Vulgo— River Crow-foot. 



Root perennial. Stems numerous from the root, procumbenlly floating, 9 to 18 

 inches long, very slender, smooth, j >inted, branching, and usually throwing out 

 a couple of filiform roots at the joints. Leaves alternate, 1 at each joint, di-or 

 trichotoraously multifid, smooth, deep green; segments half an inch to an inch 

 1 >ng, filiform or capillaceous, aggregated in little bundles or tufts; petioles 1 third 

 of an inch to an inch long, dilated and sheathing at base. Peduncles opposite the 

 leaves, 1 to 2 inches long. Sepals elliptic-ovate, concave, striate. Petals while, 

 or ochroleucous, yellow at base, obovate-oblong, somewhat cuneatc, with a nec- 

 tariferous pore at base. Carpels few, smoothish, slightly rugose, with a short and 

 often oblique leak. 



Hob. Flowing waters; Brandy wine: frequent. Fl. June— Aug. Fr. Aug— Sept. 



Obs. I have often found this plant entirely submersed (and usually in swift 

 running water) so deep that the flowers certainly never reached the surface. 

 Prof. De Candolle enumerates 5 varieties of this species, — 1 of which Prof. Hooker 

 gives as natives of British America ; bull have only met with the present one in 

 this County. 



*t* f Carpels smooth. * Leaves undivided. 



2. R. Flammcla, L. Stem decumbent, radicating at the lower joints; 

 leaves lanceolate, or ovate-lanceolate, the lower ones petiolate, the up- 

 per ones bubsessile ; petals longer than the calyx. Beck, Bot. p. 7. 

 riot ? of Mx. 



