XXXV. UMBELLIFER^. 185 



XI. SIUM. SIUM. 



Leaves pinnate. Umbels compound, with general and partial in- 

 volucres. Calyx-teeth often prominent. Petals white, notched with an 

 inflected point. Fruit broadly ovoid, somewhat compressed laterally. 

 Carpels with 5 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 

 numerous 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 16 . - 2. S. angustifolium. 



1. S. latifolium, Linn. (fig. 415). 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'f ewer and smaller 

 segments. Umbels rather large, of 15 to 20 rays, and all terminal. Invo- 

 lucres, both general and partial, of several lancelote bracts, often toothed. 

 Fruits about 1 J lines long and broad, the small 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. 

 Fl. summer. 



2. S. angustifolium, Linn. (fig. 416). Lesser S. — 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. 

 Segments 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. JS. ereetum, Huds. 



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. latifolium in the greater part of England 

 and Ireland, but becoming scarce in northern England and eastern Scot- 

 land ; in west Scotland it has been found only in Wigtown. Fl. 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 

 prominent ribs, 2 or 3 vittas under each interstice, and several vittas on 

 the inner face. 



The genus, as now usually limited, contains a considerable number of 

 species, chiefly from the Mediterranean region and west-central Asia. 



