356 



MESSES. CTEIL WEST AND H. TAKEDA ON 



the lobe a root is differentiated, the narrower the zone of cortical parenchyma it has to 

 traverse before reaching the surface ; it follows, therefore, that in any given series, all 

 the roots of which are differentiated simultaneously, that root which has to travel the 

 shortest distance before reaching the surface, e. g.y root 9 of series 9, represented in 

 text-fig. 13, will be the first of that series to emerge from the cortex. As a result of 

 the regular succession in the appearance of the roots of any series at the surface of the 

 lobe, together with the more rapid centripetal production of secondary cortical cells in 

 tlie centre of the lobe, the roots in this region are carried towards the outer margin of 



Text-fig. 14. 



« 



ifFV 



■ - ycf? ... 



-' /or -.. 



■■'" ^C" <> 





Isoeies japomca. Diagram showing theoretical arrangement of the roots on one half of a lobe of the caudex. 



The roots are numbered as in text-fig. 11. 



the lobe (text-figs. 12, 13), th 



remainin 



B 



of each series emersin 



gle of the furrow 



0""D 



at a 



point 



In this connection a brief description of the root-arrangement of those species, such 

 I. lacmtris, I. echinosj^oi-a, etc., which generally possess a bi-lobed caudex, may not 



be out of pi 



It is well known that the basal portion of the stele (i.e., rhizopho 



stele) of these bilobed forms has t^' 

 furrows of the caudex. 



which lie 



the 



of the 



main 



In a median longitudinal section of the 



dex cut parallel 



with the furrows, the rhizophore-stele appears 

 cf. Von Mohl, 24, p. 183, Taf. 3. figs. 4, 9). 



shaped (text-figs. 2, 15 



also 



