THE CRUCIFORM FAMILY. 57 



(in the form of a cross,) is from the flowers being 

 formed invariably of 4 distinct petals, which there- 

 fore divide in the form of a cross. And all flowers 

 thus formed, (with the exception of the Celandine, 

 and perhaps one or two more) have 6 stamens and 

 belong to the Cruciform Family. It is very easy to 

 distinguish plants of this Order, but not so easy to 

 distinguish Species; as we shall find. 



[VI. Order. CRUCIFOEM FAMILY. (Cruciferse.) 



Calyx of 4 Sepals. Petals 4. Stamens 6 (usually) 2 shorter 

 than the other 4. (tetradynamous, ) 2, of the Stamens/ solitary > 

 alternate with the petals ; 4, opposite to them, in two pairs. 

 Ovary, and style, 1. Hypogenous glands, at the base of the 

 solitary Stamens. Seed-vessel, usually, a pod or pouch. 

 2-celled (rarely one) 2 valved, the valves opposite the shorter 

 Stamens (PI. II. 5.) sometimes valveless. Seeds on marginal 

 placentas between the longer Stamens; without albumens. 

 Radicle curved.] 



Small as the seeds of most of the species are, the 

 difference in position is so marked, that they are 

 divided into 3 Sub-Orders, from this wonderful ar- 

 rangement, only. Thus 



I. SUB-ORDER. Cotyledons flat (plane) parallel to 

 the Dissepiment, and with their edges, applied to the 

 Radicle, (accumbent . o=.) 



II. SUB -ORDER. Cotyledons plane, with their backs 

 turned to the Radicle, (incumbent o||.) 



