328 COLLEGE BOTANY 



Uses. — Onions and other species of this genus, are most ex- 

 tensively iised as vegetables, for flavoring and for pickling. The 

 allyl sulphide is said to stimulate the flow of digestive juices 

 and therefore they are sometimes recommended to correct 

 troubles of the alimentary tract. Owing to their low sugar and 

 starch content, they are sometimes recommended far invalids 

 who cannot use. starchy foods. 



The genus Asparagus includesi the very important vegetable 

 of that name and a number of ornamental species. The common 

 edible asparagus (A. officinalis) has both underground and 

 aerial stems and fibrous roots. The early spring shoots are very 

 fleshy and are used extensively for food, while the later shoots 

 are allowed to grow and produce flowers and frtiits. The small 

 scales on the stems are true leaves, but clusters of filiform struct- 

 ures, known as cladopliylls, are produced in the axils of these 

 scale leaves and function as leaves. 



The flowers are small, solitary, axillai-y, perfect with a six- 

 parted perianth, six stamens inserted on perianth, ovary three- 

 angled, style short, stigxaa three-parted, the fruit a red globose 

 berry of three chambers and two seeds in each chamber, pollina- 

 tion by means of insects. 



The origin of the common asparagus is not definitely known, 

 but it was used as a vegetable by the Greeks and Romans at least 

 ,2000 years ago. It is widely distributed throughout the tem- 

 perate zones of the world and has escaped from cultivation in 

 many places. 



Asparagus is a very common vegetable, and is very popular 

 because it comes so early in the spring. It is grovsm extensively 

 throughout the country. 



The genus Smilax includes a number of species, some of 

 which are important as ornamentals, and some of which furnish 

 the sarsaparilla of commerce which is used in flavoring and 

 as a drug. 



Sarsaparilla is obtained from species growing in Mexico, 

 Central America and the northern part of South America. It 



