56 Peine— A Contribution to the 
cells become quite long, they retain throughout their brief 
existence the appearance of young procambium-cells, being 
filled with granular protoplasm enclosing large nuclei. This 
core of thin-walled elongated cells, less like a vascular struc- 
ture than the central cylinder of the larger Mosses (e. g. Poly- 
trichum), is the only indication of the differentiated root- 
structure which these plants must have possessed before 
they became parasitic. The cortical cells are approximately 
cubical, thin- walled, containing abundant protoplasm and 
large nuclei. Indeed it is a noteworthy, as well as an easily 
observed, fact that the nuclei of all the living cells of a Cuscuta 
are larger than those of the corresponding cells of its host. 
The epidermal cells and the root-hairs are slightly cutinized. 
The root having penetrated the soil for a short distance, or 
having grown sufficiently over the surface to give some sup- 
port, the now rapidly elongating stem, having grown for some 
distance out of the seed, bends at a point near its union with 
the root and thus rears its tip, still enclosed within the seed- 
coats and imbedded in the endosperm from which it draws its 
nourishment, till it becomes nearly or quite erect. The young 
stem is yellow or almost white, at any rate not green, and so 
lacking in chlorophyll that assimilation must be very slight, if 
at this stage of the plant’s history it occurs at all. Frank 1 
cites in his text-book an investigation carried on in his labora- 
tory by Temme 2 , according to which chlorophyll is present, 
not merely in quantity sufficient for spectroscopic determina- 
tion, but also for the evolution of oxygen, as proved by 
experiments with fuming phosphorus. Such investigations 
were, however, carried on with older plants, and, though 
necessarily implying the presence in the seedling of plastids 
capable of developing into chloroplastids, scarcely yield 
results which would justify our assuming that the seedling 
obtains food from any other source than the endosperm in 
which its tip is imbedded. (As to the amount of chlorophyll 
1 Frank, A. B., Lehrbuch der Botanik, Leipzig, 1892, Bd. I, p. 556. 
2 Temme, F., Berichte der deutschen botanischen Gesellschaft, 1883, P* 485. 
Also in Landwirthschaftliche Jahrbiicher, 1884, Bd. XIII. 
