294 A TEXT-BOOK OF BOTANY 



types of garden peas are those with smooth seeds and those 

 with wrinkled seeds, the former being earlier and hardier 

 (hence most common in the market), the latter better in 

 quality. Beans are of many kinds, but the common bean of 

 Europe does not succeed well in the United States. Our 

 common garden and field bean is the kidney bean, which 

 reached the United States from South America by way of 

 Europe. The lima bean is also of South American ori- 

 gin, and is most extensively grown in California. Peanuts 

 (goobers) are curiously developed and very familiar pods. 

 After the flower has fallen, its stem bends downward and 

 pushes the young pod into the sandy soil, where it matures, 

 and hence is sometimes called groundnut. Several of our 

 native legumes also have this curious habit. The peanut 

 is thought to be a native of Brazil, and is now grown in 

 all warm regions of the world. In the United States it 

 has become an important commercial crop of the Southern 

 States since 1866, being chiefly grown in Virginia, North 

 Carolina, Georgia, and Tennessee; the annual yield being 

 four million bushels. 



167. Umbellifers. This is the highest family (UmbelUf- 

 erce) of the Archichlamydeae, and the name has been sug- 

 gested by the fact that the small flowers are massed in 

 flat-topped clusters called umbels ( 139) (Fig. 224). The 

 family is distinguished also by the fact that the ovaries are 

 inferior ( 138). In general they are perennial herbs of 

 north temperate regions. Parsnips and carrots are the 

 thick tap-roots of two of the species, and celery is the 

 blanched leaf-stalks of another. Some species are charac- 

 terized by their aromatic foliage or fruit, as coriander, fen- 

 nel, and caraway; and one species yields the deadly hem- 

 lock. 



168. Other useful Archichlamydeae. Many well-known 

 ornamental plants do not belong to the representative fam- 

 ilies described above, as violets, pinks, geraniums, nastur- 



