114 Class V. Order II. 



by mistake for that, plant by drug-gists. Stem about two feet 

 high, striated, not spotted. Leaves bipinnate and at length pin- 

 natifid. The distinguishing mark of this plant is in the partial 

 involucres which consist of only three leafets which are exter- 

 nal, linear, long and pendulous, Common about the streets of 

 this city, probably introduced from Europe. July, August. 

 Annual. 



124. SISON. 

 SISON CANADENSE. L. Honeworf. 



Leaves ternate ; umbels irregular. 



Syn. CHAEROPIITLLVM CANADIAN HE. Pursh. 

 MrRRHis CANADENSIS. Nutt. 



Stem smooth. Leaves in threes, the radical ones cleft, those 

 of the stem doubly toothed, rhomboidal, smooth or shining. Um- 

 bel branched, unequal, of few rays, with no general involucre. 

 Partial umbels unequal, close, few flowered, with a minute in- 

 volucre. Flowers small, white. Seeds smooth, oblong. Chel- 

 sea beach island. July. 



125. CICUTA. 

 CICUTA MACULATA. L. American Hemlock. 



Bigeltnv, Medical Botany, PI. xii. 



Root fascicled, leaves oblong, with mucronate ser- 

 ratures. 



The root is composed of a number of large, oblong, fleshy 

 tubers, diverging from the base of the stem, and frequently being 

 found of the size and length of the finger. The root is peren- 

 nial, and has a strong, penetrating smell and taste. In various 

 parts of of the bark it contains distinct cells or cavities, which 

 are filled with a yellowish resinous juice. The plant is from 

 three to six feet high. Its stem is smooth, branched at top, hol- 

 low, jointed, striated, and commonly of a purple colour, except 

 when the plant grows in the shade, in which case it is green. 

 The leaves are compound, the largest being about three times 

 pinnate, the uppermost only ternate. Most of the petioles are 

 furnished with long obtuse stipules, which clasp the stem with 

 their base. Leafets oblong, acuminate, serrate, the serratures 



