THE ROOT. 



(39 



(fig. 19). Some roots merely reach a club-shaped 

 condition, swollen towards the apex, but quite un- 

 branched and unflattened ; such represent transitions 

 between the simply forking and the fasciated condi- 

 tion (PI. V, figs. 1 and 2). The forking and fasciated 

 roots bear a number of lateral branches which repre- 

 sent the weaker arms of each successive forking 

 which have been left behind, the same phenomenon 

 which occurs in forking stems and leaves ; a normal 

 case of this is well seen in the stem of Selaginella. 



Fig. 19. — Hedera Helix. Koots showing- incipient forking and fasciation. 



The extreme fasciated condition yields a structure 

 greatly resembling the thallus of the Alga Zonaria, 

 even having the same zone-bands (PI. V, fig. 2). 



Interesting cases of fasciation of aerial roots in the 

 orchids Aerides crispum and Phalaenopsis Schilleriana, 

 as also of the roots of aloe, have been figured or 

 described in the 4 Gardeners' Chronicle.' These 

 showed conspicuous spiral curvature, and in the case 

 of the aloe, similar transitions between simple dicho- 

 tomy and fasciation to those above-described. 



Fermond gives cases of ' fasciated lateral roots in 

 Phaseolus multijiorus, one of which was 24 millimetres 



