expressed juice was not limpid, but thick, mucilaginous and ropy.
Under the microscope the raphides seemed as plentiful as in the case
of the two acrid plants. When diluted with water and shaken with
ether, there was no visible turbidity in the supernatant ether, and
when a drop of the ether was allowed to evaporate on a glass slide,
only a few isolated crystals could be seen. From this it will be seen
that in this case the raphides did not separate from the mucilaginous
juice to be held in suspension in the ether. A great deal of time and
labor were spent in endeavoring to separate the crystals completely
from this insoluble mucilage, but without avail. With the tradescantia
similar results were obtained.

From these experiments the absence of acridity in these two plants, in
spite of the abundance of raphides, may readily be explained by the
fact that the minute crystals are surrounded with and embedded in an
insoluble mucilage, which prevents their free movement into the tongue
and surface of the mouth, when portions of the plants are tasted.

The reason why the Indian turnip loses its acridity on being heated
can be explained by the production of starch paste from the abundance
of starch present in the bulbs. This starch paste would evidently act
in a manner similar to the insoluble mucilage of the other two plants.

So also it can readily be seen that when the bulbs of the Indian
turnip have been dried, the crystals can no longer separate from the
hard mass which surrounds them, and consequently can exert no irritant
action when the dried bulbs are placed against the tongue.--_Jour. Am.
Chem. Soc._

* * * * *