1904] BRIEFER ARTICLES 217 
and parasite as in natural semiparasites like Viscum and Phoradendron. 
The roots grew downward through the internodes and nodes, but did not, 
in any case here reported, reach the level of the soil, much less reach the 
soil itself. The roots branched much less freely than normal soil roots, 
were closely applied to the walls of the hollow internodes, and did not at 
any point fill the cavity of the internode. 
- That this much reduced root-system sufficiently supplied the small 
bean-pea plants with water is proved by an accidental experience. The 
potted bean plants one day became dry enough to wilt, but the peas were 
perfectly fresh and turgescent. The beans recovered promptly when 
watered and the peas at no time showed any ill effects. 
It may be claimed that the smaller size of the pea-plants grown on beans 
is due to hard times—to mechanical interference with the normal growth 
and development of the root system. This may be true, but it is equally 
true that there are mechanical hindrances to the growth, extension, and 
development of the root systems of all phanerogamic parasites. In this 
respect, therefore, the cases are parallel. 
In the aerial parts of Viscum, Phoradendron, and Arceuthobium,? 
Xewophytic characters are evident.s These did not appear in my bean- 
Peas, unless the smaller number and size of the leaves and the shortened 
mternodes may be so called. Xerophytic characters may appear later if 
peas are cultivated on beans through a series of generations. I hope to 
be able to do this, under conditions which can be carefully controlled, and 
especially where my plants may at least be protected against ordinary 
accident, ' 
_ Thave-tried various other seeds on Vicia Faba, including Vicia Faba 
itself, but peas have so far done best and Vicia Faba has proved to be the 
best host for them. A more succulent plant with solid stem, however, 
would be better. This I shall try in the future. 
Though this is an incomplete account of experiments far from con- 
cluded, it has seemed best to put this much of my work on record. It may 
oe light on questions regarding the beginning of parasitism, the 
madi te Cftects of removing the roots of green plants from their normal] 
um, the soil, and compelling these green plants to supply themselves 
wit : 
Mei Water and mineral matters from other plants.—GEoRGE J. PEIRCE, 
njord Universit , California. 
*t 
“*pect presently to publish a paper on Arceuthobium. 
3 
28- CANNon, W. A., The anatomy of Phoradendron villosum. Bull. Torr. Bot. Club 
* 374-390. pls, 27-28. 1901 : 
