ERRATA. 
P. 383. The sentence beginning on line seven from bottom should read : ‘ Some- 
times the protoxylem directly abuts upon the endodermis, but it may also be 
separated from it by a layer of parenchymatous (pericyclic) cells,’ &c. 
P. 391. The clause beginning on line six from bottom should read : ‘nevertheless 
it may exhibit a variation which recalls that already described for the primary and 
first-formed lateral roots, namely, that the protoxylem of many or even all of the 
rays may abut immediately upon the endodermis (which is sharply marked from 
the first) whilst in others it is separated from it by one or more layers of pericyclic 
parenchyma.’ 
