Stigmarian Rootlets . 561 
Stigmarian rootlets. In the rootlet represented in Fig. 1 1 , as 
in some other rootlets which are cut longitudinally, there can 
be seen running obliquely between the parenchymatous sheath 
of the inner cortex (i. c.), which surrounds the stele, and the 
outer cortex (o. c.) a delicate strand of tracheids ( tr .) sur- 
rounded by a layer of parenchymatous cells. Though its 
origin from the central stele is not seen, there can, I think, 
be no doubt as to the identity of this delicate strand with the 
vascular branch described by Renault. In confirmation of 
this view, it may be mentioned that the position of this strand 
of tracheids is on that side of the rootlet which lies nearest to 
the protoxylem. Hence it would not be wrong to assume 
that it was probably connected with the protoxylem elements 
in the same way as in the rootlet figured by Renault. 
Another point of agreement with Renault’s figure is the 
small process (p) passing off from the parenchymatous sheath 
which would seem to have connected it with other parenchy- 
matous cells of a delicate character, forming lacunar or trabe- 
cular tissue, remnants of which can be seen near the upper 
end of this strand, as also in Renault’s figure. 
For all these reasons we are I think justified in assuming 
that the isolated vascular branch seen in Fig. 1 is similar to 
that which Renault figures as connected with the protoxylem 
of the stele, and which in a very different type of rootlet I 
also found connected with the protoxylem elements. 
Roth Renault’s figure and my previous one were taken from 
transverse sections, and the fact that in the latter the vascular 
branch ran only for a short distance transversely into the 
middle cortex may be taken to indicate that after leaving 
the stele its course must have been more or less oblique, 
a supposition which is borne out by the longitudinal section 
as represented in Fig. 1. 
But while the inner connexion of these vascular branches 
with the protoxylem of the central cylinder was established 
by Renault, very little has been known about their termina- 
tion. Renault, rather naturally, was inclined to regard them 
1 Hick Collection, No. 107. 
