, he at once jumped
from the bed; if directed to repeat certain words, he said them, and
so on.

I am not able to give any certain explanation of the phenomena of
miryachit or of the "Jumpers," or of certain of those cases of
sleep-drunkenness which seem to be of like character. But they all
appear to be due to the fact a motor impulse is excited by perceptions
without the necessary concurrence of the volition of the individual to
cause the discharge. They are, therefore, analogous to reflex actions,
and especially to certain epileptic paroxysms due to reflex
irritations. It would seem as though the nerve cells were very much in
the condition of a package of dynamite or nitro glycerin, in which a
very slight impression is sufficient to effect a discharge of nerve
force. They differ, however, from the epileptic paroxysm in the fact
that the discharge is consonant with the perception--which is in these
cases an irritation--and is hence an apparently logical act, whereas
in epilepsy the discharge is more violent, is illogical, and does not
cease with the cessation of the irritation.

Certainly the whole subject is of sufficient importance to demand the
careful study of competent observers.

* * * * *

THE GUM DISEASE IN TREES.[1]

[Footnote 1: Communicated to the _Medical Times_ by Sir James Paget.]

An essay by Dr. Beijerinck, on the contagion of the gum disease in
plants, lately published by the Royal Academy of Sciences at
Amsterdam, contains some useful facts. The gum disease (_gummosis,
gum-flux)_ is only too well known to all who grow peaches, apricots,
plums, cherries, or other stone fruits. A similar disease produces gum
arabic, gum tragacanth, and probably many resins and gum resins. It
shows itself openly in the exudation of thick and sticky or hard and
dry lumps of gum, which cling on branches of any of these trees where
they have been cracked or wounded through the bark. Dr. Beijerinck was
induced to make experimental inoculations of the gum disease by
suspicions that, like some others observed in plants, it was due to
bacteria. He ascertained that it is in a high degree contagious, and
can easily be produced by inserting the gum under the edge of a wound
through the bark of any of the trees above named. The observation that
heated or long boiled pieces of gum lose their contagious property
made it most probable that a living organism was concerned in the
contagi