84 THE CRUCIFER FAMILY. [Sisymbrium, 



slightly toothed lobes, the terminal one 1 to 1 inches long, the 

 others smaller, often curved backwards ; the upper leaves sometimes 

 undivided and hastate. Flowers very small and yellow. Pods about 

 6 lines long, thick at the base, tapering to the point, more or less 

 hairy, almost sessile, and closely pressed against the axis, in long, 

 slender racemes, the midribs of the valves almost as prominent as in 

 Erysimum. 



In waste places, and by roadsides, common throughout Europe and 

 Russian Asia, except the extreme north. Abundant in Britain, rarer in 

 the north of Scotland. FL summer. 



2. S. Irio, Linn. (fig. 71). London Rocket. An erect annual, with a 

 hard stem, a foot high or more, and glabrous or nearly so. Leaves 

 deeply pinnatifid or pinnate, the lobes or segments lanceolate, more 

 numerous and larger than in S. officinale. Flowers small and yellow. 

 Pods on more or less spreading pedicels, 1 \ to 2 inches long, often all 

 turned to one side, forming a dense, erect raceme. 



In waste places, and by roadsides, in central and southern Europe to 

 the Caucasus. Rare in Britain, and chiefly recorded from the neigh- 

 bourhood of London, Berwick, and Dublin. Fl. summer. [Called London 

 Rocket from having sprung up amongst the ruins of the Fire of London 

 in 1666.] 



3. S. Sophia, Linn. (fig. 72). Flixweed. An erect annual, a foot 

 high or rather more, not so coarse as the last two, and somewhat hoary 

 with a very short down. Leaves two or three times divided into numerous 

 short linear segments. Flowers small and yellow. Pods slender and 

 glabrous, 9 to 12 lines long, on slender, spreading pedicels, forming loose, 

 terminal, erect racemes. 



In waste places, by roadsides, &c., in Europe and northern Asia, 

 from the Arctic Circle to the Mediterranean, the Caucasus, and 

 Himalaya, and in northern America ; thinly scattered through Britain. 

 Fl. summer. 



IX. ALLIARIA. ALLIARIA. 



A single species, associated by some with Sisymbrium, by others with 

 Erysimum ; differing from the former by the valves of the pod, with a 

 prominent midrib, as in tirysimum ; from the latter by white flowers, 

 and a more cylindrical pod ; from both by a peculiar habit of foliage, 

 and by the striate seed, of which the short stalk is more distinctly 

 expanded (within the pod) into a broad white membrane. 



1. A. officinalis, Andrz. (fig. 73). Garlic-Mustard, Sauce-alone. 

 An erect annual or biennial, or sometimes of longer duration, 1 to 3 

 feet high, smelling strongly of garlic when rubbed, glabrous, or with a 

 few long hairs on the stem and the edges of the leaves. Lower leaves 

 on long stalks, orbicular and crenate ; those of the stem on shorter 

 stalks, cordate, ovate, or triangular, coarsely toothed, 2 to 3 inches 

 long and broad. Flower small and white. Pods on short, spreading 

 stalks, stiff and glabrous, 1 to 1 inches long, nearly cylindrical, but 

 with a very prominent midrib on each valve. Sisymbrium Alliaria, 

 Scop. Erysimum AUiaria, Linn. 



Under hedges, in shady waste or cultivated places, over the greater 

 part of Europe and western Asia, but not Arctic. Frequent in Britain, 

 but decreasing much in northern and western Scotland. PL spring. 



