186 THE UMBELLATE FAMILY. [ Carwm. 
abundant in some parts of Hertfordshire, Cambridgeshire, and adjoining 
counties. Not recorded from Ireland. Fl. summer. 
XI. SIUM. SIUM. 
Leaves pinnate. Umbels compound, with general and partial involucres:. 
Calyx-teeth often prominent. Petals white, notched with an inflected 
point. Fruit broadly ovoid, somewhat compressed laterally. Carpels with 
© slender ribs, and several vittas under each interstice. 
A small genus spread over almost all temperate regions of the globe; 
resembling Apium in the shape of the fruit, but with the calyx-teeth 
usually prominent as in Cicuta, and differing from both in the more nume- 
rous vittas. 
Stem usually 3 or 4 feet. Umbels all terminal; rays usually 15 
to 20 . 1. S. latifolium. 
Stem much branched, seldom above 2 feet. Umbels mostly 
lateral ; rays usually 10 to 15 é . 2. 8. angustifolium. 
1, S. latifolium, Linn. (fig. 418). Broad Sium, Water Parsnip.—A 
glabrous perennial, with a creeping rootstock, and stout erect stems 2 to 
4 feet high. Lower leaves very long, with 6 to 20 pairs of ovate-lanceolate 
segments, sessile on the common stalk, toothed or rarely slightly lobed, 
often 2 to 4 inches long; the upper leaves shorter, with fewer and smaller 
segments. Umbels rather large, of 15 to 20 rays, and all terminal. Invo- 
lucres, both general and partial, of several lanceolate bracts, often toothed. 
Fruits about 14 lines long and broad, the smail pointed teeth of the calyx 
usually very distinct. 
In wet ditches and on the edges of streams throughout Europe, except 
the extreme north; replaced in Asia by a closely allied species or variety. 
In Britain, not unfrequent in southern and central England and in Ireland, 
more rare in the north, and very local in southern Scotland. 7. summer. 
2, S.angustifolium, Linn. (fig. 414). Lesser Sium.—Resembles the 
S. latifolium, but is not so tall, more. branched and leafy, seldom 2 feet 
high, and in dried-up ditches often less than a foot, and decumbent. Seg- 
ments of the leaves smaller, 8 to 10 pairs in the lower leaves, fewer in the 
upper ones, from ovate to ovate-lanceolate, more deeply and sharply toothed 
or lobed than in S. latifolium. Umbels more numerous, smaller, on 
shorter peduncles, mostly lateral, with 8 to 12 or 15, rarely more, rays. 
Involucral bracts, varying from broad lanceolate to linear, often toothed. 
Fruit smaller than in S. latifolium, the ribs less prominent, the vittas less 
superficial, the calyx-teeth very minute. 
In wet ditches and shallow streams, throughout temperate and southern 
Europe and western Asia, from south Sweden to Persia. In Britain rather 
more common than S. latifoliwm in the greater part of England and ea 
land, but becoming scarce in northern England and eastern Scotland ; 
west Scotland it has been found only in Wigton. FV. summer, 
XII. PIMPINELLA. . PIMPINEL. 
Leaves dissected. Umbels compound, without involucres. Petals 
broad, notched, with an inflected point. Fruit short, somewhat laterally 
compressed, without visible calycine teeth. Carpels with 5 scarcely pro- 
iieneae ws) 
