VARIETAL CHARACTERISTICS OF SOY BEANS. 13 



In other varieties the stems and branches, especially the elongated 

 terminals, are more or less twining and usually weak, so that the 

 plant is only suberect or even procumbent. (Pis. I, II, and III.) 

 In the bushy forms the internodes may be short, in which case the 

 pods are more or less densely crowded or elongated, causing the pods 

 to be scattered. Varieties with elongated internodes are usually 

 slender and the pods small, but this is by no means universal. The 

 form of the plant may be greatly modified by thickness of planting, 

 as the development of the branches is inhibited by close planting and 

 encouraged by isolation. 



FOLIAGE, 



There is wide variation in the leaves of soy beans, involving shape, 

 size, color, and degree of persistence. These characters merge by 

 insensible degrees, so that they are useful in differentiating varieties 

 only in extreme cases. In shape, the leaflets are usually ovate- 

 lanceolate, but in some varieties are narrowly lanceolate or almost 

 linear; in others, nearly orbicular. They vary in length from 1 inch 

 to 5 inches. In color they are usually pale, but some are dark green. 



In nearly all varieties of soy beans the leaves commence to turn 

 yellow as the pods begin to ripen and commonly all have fallen when 

 the pods are mature. On this account it is difficult to harvest the 

 crop for grain and save all the foilage as well, but this is possible with 

 many varieties. A few sorts, like the Wisconsin Black, retain their 

 leaves green until all or nearly all of the pods are mature. 



Additional leaflets occur not uncommonly in several varieties. 

 This seems to be especially true with early sorts from Siberia, on 

 which leaves with four or five leaflets are frequently seen. 



PUBESCENCE. 



All soy beans are hairy plants, and there is but little difference in 

 the amount of hairiness. No smooth variety has thus far been 

 obtained, the nearest approach to it being No, 22876, from Tokyo, 

 Japan, The pubescence occurs in two colors, white or gray and tawny, 

 which behave in Mendelian fashion, the tawny being dominant. The 

 tawny pubescence is nearly always on tawny-colored or dark pods and 

 the white pubescence on grayish pods. Many cases occur where two 

 varieties differ wholly or mainly in the color of the pubescence. In 

 some instances these have been segregated; in others the mixture 

 is evident. In such cases one color usually predominates, the pres- 

 ence of the other being due to casual hybridization, 



FLOWERS. 



Soy-bean flowers occur in two colors, purple and white. Certain 

 varieties can be distinguished most readily by this character. In a 

 number of the lots tested both colors of flowers occur, the plants 



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