E 
si 
E 
1876.] Botany. 233 
a cedar-tree (Juniperus Virginiana L.) to the top, and, no longer finding 
anything to adhere to, sent out free fruiting branches nearly half an inch 
thick. Of this I took several measurements. Two and a half feet from 
the ground, where the diameter was 104”, the distance from centre of 
pith to inner edge was 8}/’, and to outer 2". A foot lower the propor- 
tion had decreased to that of 9’ to 2)’ ina diameter of 11}. Ten 
inches lower still it had further decreased, so that the pith was still 9!’ 
from the inner, but 44} from the outer margin. The ratios between the 
two distances in descending the stem were therefore, respectively, 43, 
33, and 2. Above the first-mentioned point the position of the pith re- 
mained nearly unchanged. 
A very large vine, nearly four inches in diameter, gave less marked 
results. Sections not being exactly circular, linear measurements could 
not be relied upon, but a line drawn through the heart, parallel to a tan- 
ever, exhibited the extreme of the phenomenon, the cellular dot ap- 
Proaching to within a fourth of a line of the membranous bark. Indeed, 
so anxious did it seem to remove itself to the greatest possible distance 
from the tree that for the greater part of the way there was a manifest 
ridge running along the back of the stem, in which the pith was situated. 
These facts, however, uniform and singular as they are, could not in 
themselves be regarded as sufficient to demonstrate the absorption of sap 
from the supporting trees by the rootlets. To satisfy such an assump- 
Hon certain tests must be applied. The first that, suggested itself to me 
Was that of making similar observations at points where, for any reason, 
the vines had swung loose from their support, so that no connection ` 
should exist by means of the rootlets. Many such cases were found and 
examined. The larger vine first referred to, which at a distance of two 
feet and a half from the ground, where the attachment was firm, meas- 
ured 84" to the inner and 2" to the outer margin, giving a ratio of 4} 
= the measurements, had the pith located 54” from the inner and 
32!" from the outer margin, a ratio of 13, at a point some six feet higher, 
Where it had become detached. In this example it was evident that 
there had formerly existed some degree of attachment. At other points 
© same vine, bearing the berries and showing no tendency to cling, 
ere was no appreciable eccentricity. Another small vine, which ad- 
t 
