'94 



CRUCIFERAE. 



Vol, II. 



Brassica Napus L. (Rape) is like the preceding species but has all the leaves glabrous ; some- 

 times found in waste places, 



Brassica oleracea L. (Cabbage) is occasionally spontaneous after cultivation. 



Brassica japonica Siebold, occasionally spontaneous after cultivation, has laciniate, often 

 crisped leaves. 



42. DIPLOTAXIS DC. Syst. 2: 628. 1821.. 



Annual, biennial or perennial herbs, similar to the Mustards, with basal and alternate 

 pinnatifid or lobed leaves, and rather large yellow flowers in terminal racemes. Silique 

 elongated, linear, flat or flattish, short-beaked or beakless, the valves mostly i-nerved. Style 

 usually slender Seeds in 2 complete or incomplete rows in each cavity of the silique, margin- 

 ginless; cotyledons conduplicate. [Greek, referring to the double rows of seeds.] 



About 20 species, natives of the Old World, the following fugitive or adventive in our territory. 

 Type species : Diplotaxis tenuifolia (L.) DC. 



Perennial ; stem leafy nearly to the inflorescence. 

 Annual ; leaves mostly basal, oblanceolate. 



D. tenuifolia. 

 D. muralis. 



I. Diplotaxis tenuifolia (L.) DC. Wall 

 Rocket. Fig, 2108. 



Sisymbrium tenuifolium L. Cent. PI. i: i8. 1755. 

 Diplotaxis tenuifolia DC. Syst. 2: 632. 1821. 



Perennial, glabrous or nearly so, somewhat 

 glaucous, stem branched, bushy, leafy, l°-4° 

 high. Leaves pinnatifid, often nearly to the 

 midrib, thin, the lower 3-6' long, the lobes dis- 

 tant or close together, mostly narrow ; racemes 

 elongated in fruit, loose; flowers 8"-io" broad; 

 pods I'-ii' long, about li" wide, nearly erect; 

 pedicels slender, io"-2o" long in fruit. 



In waste places and ballast. Nova Scotia to On- 

 tario,^ New Jersey and Pennsylvania, chiefly about 

 the cities and in California. Adventive from Eu- 

 rope. Cross-weed. June-Aug. 



2. Diplotaxis muralis (L.) DC. Sand 

 Rocket. Fig. 2109. 



Sisymbrium miirale L. Sp. PI. 658. 1753, 

 Diplotaxis muralis DC. Syst, 2: 634, 1821. 



Annual, branched from the base, sparingly 

 hispid or glabrous, the slender branches l''-2° 

 high, leafy only below. Leaves oblanceolate, 

 sinuate-Iobed or sometimes pinnatifid, 2'-^' 

 long, narrowed at the base, mostly slender- 

 petioled; fruiting racemes long, loose; flowers 

 6"-8" broad; pod about i' long and 1" wide, 

 erect, flattish ; fruiting pedicels 4"-8" long. 



In waste places and ballast. Nova Scotia to 

 Pennsylvania and in Bermuda. Adventive from 

 Europe. Flix- or cross-weed. June-Aug. 



43. RAPHANUS [Tourn.] L. Sp. PI. 669. 1753. 



Erect branching annual or biennial herbs, with lyrate leaves and showy flowers. Silique 

 hnear, coriaceous, fleshy or corky, constricted or continuous and spongy between the seeds, 

 indehiscent. Style slender. Seeds subglobose; cotyledons conduplicate. [Greek, quick- 

 appearing, from its rapid germination.] 



A genus of about 6 species, natives of Europe and temperate Asia. Type species : Raphanus 

 sativus L, 



Flowers yellow, fading white; pod longitudinally grooved, 4-10-seeded. i. R. Raphanistrum. 



Flowers pink or white-; pod not longitudinally grooved, 2-3-seeded. 2. R. sativus. 



