102 



SYMBIOSIS. 



much and become club-shaped or dichotomously branched 

 bodies without power of division, which may be designated 

 " bacteroids." ^ Brunchorst found the contents of the bacteroids 



Fig. 23. — KhkobiuM Uguminomrum. Root-tubercles on Robinia Fsemlacacia 

 (v. Tubeiif iihot.) 



to disappear at the time of the fruit-formation of the host- 

 plant. A small number of microbe-bodies still remain, according 

 to Frank's observations, capable of division, and these, after 



' According to M(3ller, they undergo fatty degeneration. 



