268 UMBELLIFERiE. ' Cicttta. 



Root as in the preceding species, but smaller. Stem 2-3 feet high, branching, striate, 

 glaucous. Lower leaves on long petioles ; upper ones nearly sessile, with sheathing petioles : 

 segments usually not more than a line wide, the margin furnished with salient teeth, and also 

 minutely serrulate. Bulbs about 2 lines long, ovate, acute, compressed, often several crowded 

 close together, but always alternate, forming short spikes in the axils of simple and sometimes 

 nearly opposite leaves : each bulb is a short branch or bud, the axis of which is thick, fleshy, 

 and invested with several scales or rudimentary leaves. Umbels small, in the forks of the 

 stem, about 12-rayed. Involucre none. Involucels of 5 - 6 small lanceolate leaflets. Flowers 

 mostly abortive. Fruit not half as large as in the preceding species, only one of the carpels 

 usually ripening : ribs nearly equal, thick, but not very prominent. 



Swamps, and in ditches and on the margin of ponds ; common in the northern and western 

 part of the State ; rare in the neighborhood of New-York. Fl. August. Fr. September - 

 October. The veins of the leaves, as in C. maculata, terminate in the notches of the serratures. 



7. SIUM. Linn. (Tpaitly) ; Endl. gen. 4:413. water parsnep. 



[Prom the Celtic word siw, signifying water ; its usual place of growth. Theis.] 



Calyx-teeth small or obsolete. Petals obovate or emarginate, with an inflexed point. Fruit 

 ovate or nearly globose, somewhat didymous, crowned with the depressed stylopodium. 

 Carpels with 5 rather obtuse ribs, and usually with several vittae in the intervals. Seeds 

 somewhat terete. — Perennial, mostly aquatic herbs. Leaves pinnately divided ; segments 

 toothed or serrate : submerged leaves finely divided. Umbel and umbellets many-rayed. 

 Involucre many-leaved. 



1. SiuM LATiPOLiuM, Linn. Broad-leaved Water Parsnep. 



Root creeping ; stem sulcate-angular ; segments of the leaves lanceolate, acuminate, serrate, 

 rarely pinnatifid ; teeth of the calyx elongated (DC). — Linn. sp. 1. p. 251 ; Nutt. gen. 1. 

 p. 186 ; Bigel. fl. Bost. p. Ill ; Torr. fl. I. p. 311 ; DC. prodr. 4. p. 124 ?; Hook. fl. 

 Bor.-Am. I. p. 262 ; Torr. ^ Gr. fl. N. Am. 1. p. 611. S. occidental, Nutt. mss. 



Stem 2-4 feet high, branching. Segments of the leaves varying in breadth, but sometimes 

 almost ovate-lanceolate ; in the lower leaves, when submerged, pinnatifid or finely cut. In- 

 volucres of 6-12 narrowly lanceolate and usually reflexed leaflets. Umbels terminal. 

 Calyx-teeth very minute. Ripe fruit not seen. 



Swamps ; rather common. July - August. 



2. SiuM LiNEARE, Michx. Narrow-kaved Water Parsnep. 

 Stem sulcate-angular ; segments of the leaves linear-lanceolate and linear, acutely and finely 



serrate.— Mtc^./. I.p.l67; Nutt. gen. I. p. 186 (excl. syn, PwriA); Torr.fl. l.p.311; 



