XII 



EQUISET1NEM 



461 



A). The growth is stronger at certain points, which, according 

 to Rees, have a definite relation to the early divisions. Thus in 

 E. scirpoidcs the teeth are always three, and correspond to the 



A. 



FIG. 268. Transverse section of a young vegetative shoot just below the apex, X26o; B, 

 outer part of a section lower down, X26o; pr, procambial zone; C, young vascular 

 bundle, X$2o; t, primary tracheids. 



primary nodal cells; in E. arvense there are six or seven, in 

 the first case corresponding to the sextant cells, in the latter to 

 the sextant cells plus the first division in one of them. In the 



