16 Wilson—Observations on 
well as Fig. 4 showed by higher magnification the spiral 
trachee, which make up about half of the fibro-vascular 
bundles. The dark spots at the base of all these figures are 
the sclerenchyma masses, which just below these buds make 
up almost the entire mass of the tubercle. 
Each cell of the parenchyma of the shoot, in addition to a 
well-defined nucleus and nucleolus, contains from one to seven 
clear spherical, highly refractive bodies, on which even hydro- 
chloric acid made no visible impression. Nevertheless, a set 
of sections left over night in the acid had in the morning 
scarcely a granule left, while another set which remained in 
alcohol over night still retained them. 
These bodies are most numerous in the apex of the stalk. 
Further down they have lost their spherical outline, look to 
be disintegrating and finally disappear. About the region 
where they begin to disappear the patches of sclerenchyma 
begin to appear. 
The bundles are well differentiated almost to the apex. 
They are made up, in about equal halves, of xylem and phloem, 
the former consisting of spiral tracheze and wood cells. In the 
adult phloem a few sieve tubes are found. The relatively 
large amount of phloem is interesting and characteristic of | 
parasites in general. For obvious reasons such a plant does 
not need much wood, and the rather large amount in this 
case has some relation to the fairly abundant stomata, which 
are so often lacking in other plants cf a similar habit. 
Cross sections of a very young rhizome, just before it leaves 
the tubercle, seem to indicate that the outer row of bundles is 
first formed and that the inner circle is developed slightly 
later. Nevertheless, since the inner row represents the normal 
group of bundles, this is so contrary to what might be ex- 
pected that my evidence seems to me scarcely to justify more 
than the suggestion that the order of development may be as 
indicated. 
Chatin figures a third row of bundles—leaf-trace bundles 
