99 
nut or hickory leaves are being coated with it, yet 
no signs of it appear on those trees during a whole 
summer. If the leaves of those trees that are coated 
with this dew are examined with a glass, not the least 
trace of punctured leaves is any more observable than 
in those not so coated ; consequently this dew can- 
not be the juices sucked by the aphides from the leaves, 
and undergoing a chemical change in the stomach, and 
ejected as an excrementitious substance in the form of 
honey. If such quantities of juice were extracted in a 
single night from the leaves as to coat them completely 
over, and even drip from the leaves beneath the tree, .as I 
have repeatedly seen, would not these leaves present in 
a few days a shrivelled and dried appearance ? — which 
is not the case. They retain all their lustre after, as 
before, such dew is found upon their surfaces. What- 
ever may be the truth of the subject, I shall readily 
yield to it as soon as unquestionable facts are presented. 
It does not hardly seem probable that it can be an exu- 
dation from the leaf, as it occurs at a time when the' 
leaves are quite mature, and in dry weather when a 
superabundance of the circulating juices would be 
more likely to be retarded than accelerated, at least to 
that degree that would cause extravasation of the circu- 
lating fluids. If such was the case would it not be 
found on the under as well as the upper surfaces of the 
leaves ? Would it not also be found on leaves that were 
shaded, as well as on those exposed ? I am aware that 
a theory or hypothesis assumed, may not always be 
reliable, but I think they are sometimes ominous of 
existing facts in embryo. I shall venture to advance a 
hypothesis that may throw some more light on this sub- 
ject, or raise the question in some studious mind, to 
