140 SECOND ORDER SILIQJUOSA. 



cotyleclones flat and incumbent, with the calyx closed 

 (or not spreading), and gibbous at the base. Of this 

 genus there is one small flowered, inodorous species 

 (H. pinaaiifida) in many parts of the valley of the 

 Ohio. The leaves are acutely serrate, the upper ones 

 lanceolate, the lower often pinnatifid-lyrate. This plant 

 is very nearly related to Sisymbrium. 



In Sinapis, or Mustard, the silique is almost cylin- 

 dric ; the seeds globose, arranged in a single row ; 

 the calyx spreading ; and the cotyledones conduplicate 

 or folded together. Most of the species are common 

 weeds, but one of them is used in salad, and another 

 affords our common warm condiment of that name. 

 The genus differs but little from that of the Cabbage 

 (Brassica) ; but in the latter the calyx is erect. 



Isatis, or VVoad, used by dyers, though placed 

 here, belongs more properly to the Siliculosa. It 

 bears lanceolate, 2-valved, and rather short siliques, 

 of only one cell, in consequence of abortion, and 

 containing but 1 seed ; the valves are also carinated 

 or keeled, like a boat. The flowers are yellow, and 

 numerous ; the stem-leaves amplexicaule or embrac- 

 ing, and sagittate or arrow-shaped. 



For convenience and affinity, we find here append- 

 ed to the close of this class the genus Cleome, of the 

 natural order Capparides. It bears a 4-leaved, 

 spreading calyx, which is not deciduous ; and 4 un- 

 equal, long clawed petals. The stamina 6, unequal, 

 often connected at the base ; and the silique stipitate 

 in its calyx, consisting of but one cell, with the curv- 

 ed, shell-formed seeds attached to a filiform marginal 

 receptacle, in which character, of the silique and seed, 

 this, and the following genera, essentially differ from 

 the CRUCiFERiE. Most of them have a heavy, dis- 

 agreeable odor, and are possessed of deleterious 

 properties, which is not the case with the other plants 

 of this class. 



