LEGUMINOUS ROOT TUBERCLES 



221 



some are herbs Lupinus, Ornithopus, Cytisus, Desmodium and Laburnum 

 is a tree. II. The Phaseoleae and Trifoleae type with the bacteroidal 

 tissue undivided and central. The growing point at an early stage 

 becomes localized apically, consequently they elongate although re- 

 maining very narrow, e.g., Trifolium, and frequently the apical meristem 



FIG. 95. Roots of soy bean, showing nodules. (After Piper, C. V.: Leguminous Crops 

 for Green Manuring. Farmers' Bulletin 278, 1907, p. 20.) 



branches, so that a repeatedly branched nodule may result, e.g., Lotus 

 corniculatus. Here belong nodules of Trifolium, Phaseolus, Coronitta, 

 Lotus, Ononis, Anthyllis. III. In the Vicese type, the nodules have the 

 elongated form with a well denned apical meristem and a basal intercalary 

 zone, which produces a small amount of tissue. The nodule frequently 



