208 



NATURAL HISTORY OF PLANTS. 



meter, elsewhere of only specific value, is sufficient at times to 



Menonvillea linearis, distinguish genera. 



Lepidium comprises herbs and undershrubs, 

 glabrous or pubescent, with alternate leaves and 

 racemose flowers. Sixty or seventy species are 

 known, inhabiting the warm and temperate re- 

 gions of the whole world, but not Alpine or 

 Arctic. These species are grouped into sections, 1 

 based on the form of the siliqua valves and 

 style. 



Fig. 307. 

 Fruit dehiscing (f ). 



VII. SUJ3ULARIA SERIES. 



Awlwort 2 (Fr., Sitbulaire ; figs. 308-310) has regular hermaphrodite 

 flowers. The receptacle forms a deep cup, in the bottom of which 

 is inserted the gynseceum, while the perianth and androceum are 



Fig. 309. 

 Diagram. 



Fig. 308. 

 Habit. 



Fig. 310. 

 Long. sect, of (lower (^). 



borne on the rim, and are hence distinctly perig} T nous. The calyx 

 is formed of four free subequal sessile sepals, all similar at the base, 



1 See the Genera below. Gen. III., t. 71. — H. H„ Gen., S3, u. 76.— 



2 Subularia L., Gen., n. 799. —J., Gen., 240.— H. Bx., in Adansouia, x. 15, t. (i. 

 Endl., n. 4977.— DC, Prodr., i. 23D.— A. Gray, 



