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unknown origin, which has been cultivated in oriental countries for 

 many centuries, both as a forage plant and for the seeds as an article 

 of human diet. It is especially adapted to warm countries and is 

 extensively cultivated throughout the south, having been introduced 

 there about the middle of last century. There are many named 

 forms or cultural varieties, all of which, however, are considered by 



' 



Fig- 39- Hairy vetch (Vicia villosa). 



botanists to be derived from one species. It so readily adapts itself 

 to different soils and changes its characters so readily under cultiva- 

 tion, that there has been much difficulty in determining the limits of 

 the various named forms. The cowpeas are of three general classes, 

 according to their habit of growth, consisting of "bunch" varieties, 

 which grow erect and compact ; " runners," which start off erect and 

 then throw out running branches * and "trailers," which grow flat 

 upon the ground with long stems sometimes 15 or 20 feet in length. 

 There is also much variation in size, shape, and color markings of 

 the seeds, and in the manner in which the seeds are borne in the pod, 



