186 PENTANDRIA. DiGYlflA. 



Umbell large, many-rayed, spreading; umbellet dense, 

 subheniispheric; involucell about 8-leavcd. Leaves large, 

 often biternately pseudo-pinnate. (Seed with longitudinal 

 ulated nrjarglns, extending internally over the whole sur- 

 face of the commissure in A. triqidiiata.) Calix 5 -toothed; 

 ])etals inflected. 



Species. 1. A. triquinata. Obs. Leaves sharply and 

 incisely serrate, very smooth, lateral leaflets oblong-ovate. 

 Involucrum none. Peduncle, pedicell, and immature 

 seed, minutely pubescent. Involucell 7 or 8-leaved, leaves 

 almost filiform and subulate, longer on one side. Umbel- 

 let unequal, dense; flowers white. Petals oval, obcor- 

 dately-inflected, inflected point long and subulate. Styles 

 long and deflected. Seeds roundish-elliptic, dorsally com- 

 pressed; margin alated, ancipital; dorsal or approximat- 

 ing ridges 3, acutely margined, almost rectilinear. — Hab. 

 From Canada to Carolina. Common around Philadelphia. 

 Certainly a genuine species, and admirably according 

 virith the improved generic character of the ingenious 

 Sprengel. 



2. atropnrpiirea. 3. lucida. 



t)i this genus there are about 8 species enumerated, 

 which, excepting the above, are all indigenous to Europe. 



i]71. SIUM. Z.. (Water Parsnep.) 



Caiix obsolete. Petals cordately inflected. 

 Fruit subovate, laterally compressed, and 

 striate. 



Involucre and involucell many-leaved; leaves mostly 

 pseudo-pinnate, and serrated on the margin. Styles rather 

 long, persistent and deflected; stigmas capitate. Fruit 

 small; oblong or oval, laterally or obversely compressed, 

 giving a narrow oblong commissure. Seed ovate, gib- 

 bously convex, equally scored with 5 elevated ridges, and 

 4 intervening grooves. (Character from Sium latifolmm , 

 as it appears in America.) Nearly allied to Carum, which 

 produces an involucrum of a single leaf. 



Species. 1. S. latifolium. (Calix obsolete, and not 

 5-toothed in the American plant.) 



2. Uneare. Stem deeply grooved} leaves pseudo-pin- 

 nate, 2 to 4 pair; uppermost ternate, terminal leaflet 

 petiolate; leaflets long, sublanceolate-linear, margin eub- 

 ciliately-serrate, serratures nearly equal, small and some- 

 times rather distant, umbells terminal, (involucre and 

 involucell many-leaved.) — Obs. Stem various in height, 

 generally ,\sXh in the smaller plants, tlie serratui-es 



