SiuM. umbellifer;e. ,;ii 



with numnrou9 flowers. Involucre many- (or rarely 1-) Icavrti. Flowers 

 white. — Water Parsnep. 



1. S. lalij(jliuni (h'lnu.): root creepine; ; stem sulcate-aiicnlar ; sepinenfa 

 of the leaves lanceolate, acuminat*-, serrate, rarely pitinatifid; involiirre 

 many-leaved; teeth of the calyx elon^^aled. DC. — Linn. sprc. 1. p. 'jr,l ; 

 Bi^el.fi. Bast. ed. 2. p. Ill ; Torr. ! J\. 1. ;;. ;ni ; DC. prudr. 4. p. lu'4 • 

 Hook. Ji. Bor.-Am. \.p. 2(i2. S. occideiUale, ISutt. mss. 



0. leaflets deeply incisely serrate. Hook.! I. c. — S. argrmim, T^'utt. mss. 



Swamps, liriti.sh America (Saskatchawan), to New Jersey ! and Penn- 

 sylvania [Muhlenberg). Oreeon, IS'uttall. (i. Straits of J)a Kuca, Dr. 

 Scolder ! — We have not recently had an opportunity of examining; this plant 

 in a livinc; state, and, unfortunately, our specimens are without fruit. Mr. 

 Nuttall distinguishes the American plant from the Euroj)ean species by its 

 minute calyx-teeth, much smaller fruit, and acuminate leaflets ; hut in our 

 (flowering) specimens the calyx-teeth are not much smaller tJian in the 

 European plant, and the leaflets are not more acuminate. 



-r- 2. S. lineare (Michx.) : stem sulcate-ansjular ; segments of the leaves (4- 

 6 pairs) linear-lanceolate and linear, acutely and Hnely serrate ; leaflets of 

 the involucre 5-6, linear-lanceolate ; calyx-teeth minute ; fruit obovate. — 

 Michx. ! Jl. I. p. 167 ; Null. gen. I. p. 186 (excl. syn. Pursh) ; Torr. I fl. 1. 

 p. 311 ; DC. ! prodr. 4. p. 125 ; Hook. fl. Bor.-Am. 1. p. 262. S. tenuifij- 

 lium, Muhl.! cat. S. latifolium, Dnrlingt. fl. Ccst. p. 190.' 



p. intermedia : leaves rather broadly lanceolate. 



Swainps, Canada ! to New Jersey ! and Pennsj'lvania ! Indiana, Dr. 

 Short ! Lake Huron, Dr. Todd. Oregon, Dr. Scoultr ! Douglas. H. Middle 

 Florida, Dr. Chapman ! — Stem 2-5 feet high. Segments of the leaves usu- 

 ally linear-lanceolate,^ but often linear and 1-3 lines wide. Rays of the 

 umbel about 20. Leaflets of the involucre sometimes 2-cleft. Calyx-teeth 

 very minute and partly concealed by the projecting margin of the stylopo- 

 dium, sometimes nearly obsolete. Petals broadly obcordate, with a rather 

 blunt inflexed point. Fruit strongly ribbed. Intervals usually with single 

 vittae, but sometimes with 2, which are closely approximated or confluent. 

 Commissure with 2 vitt». — This species is by many botanists considered as 

 a variety of S. latifolium ; but our European si)ecimens of that plant difl'er 

 in the broader segments of the leaves, the elongated lanceolate calyx-teeth, 

 broader (almost orbicular) fruit, and in the greater number of vitta". The 

 S. lineare, in its few vittte, deviates indeed from the generic character of Slum, 

 as given by Koch and De CandoUe. It nearly approaches S. lancifolium, 

 Bieberst, but diflfers in the fruit. 



3. S. pusillum (Nutt. ! mss.) : " root creeping; segments of the lower leaves 

 oblong or ovate ; of the upper ones linear, short, incisely serrate, with few 

 scrraturcs ; involucre few^-leaved ; rays of tlie umbel 6-7 ; calyx-teeth 

 obsolete. 



" Wappatoo Island, Oregon. — Plant 6-8 inches high. Segments of the 

 leaves about 4 pairs ; the terminal one sometimes 3-lobed." Nuttall. — Our 

 spechi],en is w'ithout fruit. 



t Doubtful Species. 



4. iS. ? Douglasii (DC.) : stem terete ; lower segments of the leaves 3-cleft ; 

 the others petiolulate, ovate-oblong, coarsely serrate ; umbels ojjjiosite the 

 leaves and terminal, pedunculate, many-rayed; involucre none. — DC. prodr. 

 A. p. 125 ; Hook. fl. Bor.-Am. I. p. 263. 



North West America, Douglas. Lower leaves a foot and a half long. — 



