EQUISETINEJE 



461 



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

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

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



Fig. 268. — Transverse section of a young vegetative shoot just below tlie apex, X260; B, 

 outer part of a section lower down, X260; pr, procambial zone; C, young vascular 

 bundle, X520; 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 



