192 



NATURAL HISTORY OF PLANTS. 



The Wild Mustard or Charlock 1 (Fr., geneve commun ; figs. 238- 

 241) is another Brassica, which has been made into the genus 

 Sinapistrtun- because it has a caducous style like Hirschfeldia, from 

 which it differs however in having nearly globular seeds. Dip/o- 

 taanSy has also been separated from Brassica, differing, as implied by 

 the name, in having the seeds in two rows in each cell; but the 

 character is far from constant in this group. It contains some 

 twenty species from Europe, Asia, and Africa, 4 which, as they have 

 the flower and vegetative organs of Brassica, can only form a section 

 thereof. 



Brassica (Sinapis) arvensis. (Charlock) 



Fig. 239. 

 Fruit. 



u 



Fig. 238. 

 Inflorescence. 



Fig. 240. 



Dehiscent fruit. 



Finally, Sinapidendroif includes frutescent species from Madeira, 

 and the other islands off the West coast of Africa ; 6 their siliqua is 



1 Sinapis arvensis L., Spec, 933. — DC, Fl. 

 Fr., iv. 644.— Grejt. & Godr., Fl. de Fr., i. 

 73. — Sinapistrum arvense Spach. 



2 Spach, Suit, a Buffun, \\. 343. 



3 DC, Syst. Veg., ii. 268*; Prodr., i. 221.— 

 B. H., Gen., 84, 967, n. 18.—Pendulina Willk., 

 in Linncea, xxv. 2. 



4 IiKicHii., Ic. Fl. Germ., ii. t. 81-84. — 



Hook. f. & Thoms., in Journ. Linn. Soc, v 

 171.— Boiss., Fl. Or., i. 387.— Gekn. & Godk., 

 Fl. de Fr., i. 78.— Walp., Sep., i. 187 ; v. 49 ; 

 Ann., i. 49; iv. 218; vii. 151. 



5 Lowe, PI. Madeir., 86. 



6 Hook., Icon., t. 571, 572. — Walp., Pep., i. 

 184; Ann., i. 147. 



