SECT. II 



PHANEROGAMIA 



569 



peutamcrous, with a single whorl in both perigone and androecium ; 

 P 5. A 5, CI (2-5). Reduced, unisexual flowers are not infrequent. 

 The unilocular ovary contains a basal, campylotropus ovule. Fruit, 

 a nut. Seed with a curved embryo bent around the perisperni. 



Fio. 550. — A{irostemma Glthmo. Flowei'iug shoot and fruit (A nat. size). I'oiaoxoLS. 



Many of the Chenopodiaceae are strand plants or occur on soils containing a large 

 amount of salt, such as the great Asiatic salt steppes and deserts {^*). The Spinach 

 {S'finacia oleracca) and the Summer Spinach (^S". glabra) are used as vegetables. 

 The Sugar Beet {Beta vulgaris, var. raim) (Fig. 548) is a plant of great economic 

 importance. It is a biennial plant, and in the first season forms a thick, swollen 

 root bearing a bud consisting of a number of thick-stalked, entire, succulent, and 

 often crisped leaves. From this rosette of leaves there springs in the second season 



