724 Microscopic Crystals contained in Plants. (October, 
are stellate forms consisting of four or six points, and have a yel- 
low color. This test requires care, as too much heat seems to dispel 
the crystals, 
The latter (carbonic) acid I detected in the usual manner with 
acetic acid. 
The three acids mentioned above are the only ones that I 
found. Dr. Gray, in his “ Structural and Physiological Botany,” 
page 60, reports sulphuric acid. 
The tests applied for the base were the same as those given in 
Douglas and Prescott’s “ Qualitative Analysis,” but the only base 
found was calcium. The methods of testing given above were 
followed in nearly all cases. Where there is any change it will be 
mentioned in its proper place. 
I will now give the results of my own work, commencing with 
the order Aracez; in this order the raphides are abundant and 
large, and the cells that contain them are much elongated. The 
bundles contained from ten to twenty-eight crystals. The number 
was noted in twenty specimens and the average, twenty-five, 
taken frora the results. Raphides were found in all parts of the 
plant Arisema triphyllum; they varied some in size, but were, on 
the average, about y} oth of an inch long and qobgvth in diameter. 
The raphis-cells were very large and elongated and easily distin- 
guished from the surrounding ceils. ; 
Dracontium, another species of the same genus as the above, 
showed no material difference in the position, size and number of 
the crystals from the first species. 
In Symplocarpus fætidus, or skunk’s cabbage, the crystals were 
as common as in Arisæma, but were, on the whole, somewhat 
larger, and were found, as in the above species, throughout the 
plant. The raphis-cells of this plant were about s'sth of an inch 
in length and yoysth in diameter. Some of the crystals appeared 
to be biforines, which I did not observe to be the case in any 
other species of this order. Thus if the odor of this plant can 
be overcome, it furnishes a good field for work upon this subject. 
In Acorus calamus, or sweet flag, I was not able to find a single 
raphid, and as far as I am able to find articles upon the crystals of 
this family, none have ever been reported, but time and again 
students have been disappointed in not finding them. This genus 
is thus marked off from the rest of this family, although agreeing 
with the family characters perfectly in other particulars. Dr. 
