906 SISYMBRIUM. L CLASS xv. OUDEU n. 



1. T. gla'bra. Linn. (Fig. 1046.) Long Podded Tower Mustard. 

 Stem erect; radical leaves toothed and rough, with branched hairs, 

 the upper smooth, sagittate at the base, amplexicaul ; siliqua long, 

 straight, erect. 



English Botany, t. 777. English Flora, vol. iii. p. 215. Hooker. 

 British Flora, ed. 4. vol. i. p. 252. Lindley, Synopsis, p. 23. 



Root tapering. Stem erect, from two to three feet high, round, 

 simple, or slightly branched, leafy, downy at the base, smooth upwards. 

 Leaves numerous, the radical ones oblong lanceolate, coarsely toothed 

 or sinuated, rough, with close branched or simple hairs, the upper 

 leaves lanceolate, with an arrow-shaped base, clasping the stem, 

 smooth, glaucous green, entire. Inflorescence a terminal sub-corym- 

 bose raceme, becoming much elongated. Flowers numerous, white, 

 or pale sulphur colour. Pedicles slender. Calyx oblong, of four pale 

 smooth pieces, with a narrow white border. Petals four, oblong, ovate, 

 erect. Stamens with simple filaments and orate anthers. Style very 

 short. Stigma obtuse. Fruit a long slender linear smooth erect 

 siliqua. Seeds very small and numerous in each cell. 



Habitat. Fields, banks, and road sides in various parts of England, 

 but not common ; Bowling Bay, Scotland. 



Annual ; flowering in May and June. 



GENUS XXII. SISYM'BRIUM. LINN. Hedge Mustard. 

 Nat. Ord. CRUCIF'ERJE. Jess. 



GEN. CHAR. Siliqua linear, round, or angular, valves with three 

 longitudinal ribs. Stigma obtuse, entire, or emarginate. Calyx 

 equal at the base. Seeds ovate or oblong. Cotyledons flat, 

 incumbent. (See Fig. 1, p. 872.) Name <7<rv/x/3fov, applied by 

 the Greeks to a genus of plants, but it is doubtful whether it is 

 this. 



1. S. officina'le, Scop. (Fig. 1047.) Common Hedge Mustard. 

 Leaves ruucinate, hairy, the lacine oblong, toothed ; siliqua linear, 

 awl-shaped, hairy, erect, close pressed to the stem. 



English Flora, vol. iii. p. 196. Hooker, British Flora, eel. 4. vol. i. 

 p, 254. Lindley, Synopsis, p. 29. Erysimum officinalis, Linn. 

 English Botany, t. 735. 



Root tapering. Stem erect, about two feet high, numerously 

 branched and leafy, round, rough, with deflexed hairs. Leaves rough, 

 with pubescence, lyrato-runcinate, the terminal lobe mostly broadly 

 heart-shaped, the lateral ones oblong lanceolate, or linear, all more 

 or less unequally toothed or sinuated, the upper leaves much the 

 narrowest and most slender. Inflorescence terminating the stem and 

 branches, in small clusters of yellow sub-corymbose flowers, becoming 



