CRUCIFER^E. 201 



9. Dentaria. Sepals converging. Silique lanceolate ; valves flat, 

 nerveless, opening elastically. Seeds in a single row, without mar- 

 gins. K 



2. D. DIPHYLLA (Pepper-root}. Rhizoma elongated, with a pungent 

 flavor ; stem erect, with 2 opposite ternate leaves half-way upon the stem ; 

 leaflets ovate, serrate ; flowers large, white, or very pale purple, in a terminal 

 raceme. Woods and meadows. May. 



10. Hesperis. Calyx closed, furrowed at base. Petals linear or 

 obovate, bent obliquely. Silique nearly round, or 4-sided. Stigmas 

 2, erect. Seeds 3-sided, without margins, ij. 



i. H. MATRONALIS (Rockef). Stem simple, erect ; leaves ovate-lanceo- 

 late ; stem with scattered, bristly hairs ; flowers large, purple, racemed ; 

 siliques erect, 2-4.' long, smooth. A garden perennial, 3-4 feet high. May- 

 July. 



11. Sisymbrium. Sepals equal at base. Petals with claws, entire. 

 Silique terete ; valves concave. Style short. Seeds ovate. 



i. S. OFFICINALE (Hedge Mustard). Stem erect, very branching; leaves 

 hairy ; flowers in slender racemes, small, yellow ; siliques sessile, erect. A 

 common weed, 1-3 feet high. June-September. 



12. Matthiola. Calyx closed. Sepals bi-saccate at base. Silique 

 terete. Stigmas connivent, thickened, or carinate on the back. y. 



i. M. ANNUA {Ten-weeks Stock}. Stem herbaceous, branched; leaves 

 hoary, lanceolate, obtuse, toothed ; flowers large, variegated ; silique sub- 

 cylindrical. A garden plant, 2 feet high, with soft stellate pubescence. 

 June- August. 



13. Brassica. Sepals equal at base. Petals obovate. Silique 

 compressed, with concave valves. Style short, obtuse. Seeds glo- 

 bose. 



1. B. NIGRA (Mustard}. Stem erect, smooth, branching; lower leaves 

 lyrate ; upper, linear-lanceolate, entire ; flowers yellow, I' in diameter, race- 

 mose ; siliques smooth, 4-sided, nearly i' long ; seeds small, nearly black. 

 Cultivated grounds, 3-6 feet high. June- July. 



2. B. RAPA (Turnip}. Stem and leaves deep green ; radical leaves lyrate, 

 rough ; lower stem-leaves incised ; upper, entire, clasping ; flowers yellow ; 

 seeds reddish brown. Common in cultivation as an esculent vegetable, and 

 for feeding stock. June. 



3. B. OLERACEA (Cabbage}. Leaves smooth and glaucous, fleshy, toothed, 

 or lobed, sub-orbicular ; flowers yellow, in paniculate racemes. Native of 

 sea-shores and cliffs in Europe, where it shows no appearance of a head like 

 that of the esculent varieties, thus indicating the great power of cultivation. 

 The cauliflower, broccoli, as well as the cabbage, are varieties of this spe- 

 cies. June. 



