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720 Microscopie Crystals contained in Plants. (October, 
ON THE MICROSCOPIC CRYSTALS CONTAINED IN 
PLANTS 
BY W. K. HIGLEY. 
T has been the custom to call all crystals that eccur in plants, 
whether in the cell contents, the cell-wall or even the non- 
microscopic crystals that are found in the outer portions of plants, 
by the common name “ raphides,” no matter what the form may 
be, And while giving this general name to their form, a much 
more general chemical composition was given, viz: oxalate of 
lime; and for a long time they were all supposed to have had 
this composition, and even up to the present day many writers 
have considered them thus. The decision of some seems to have 
been based on the analysis of the inorganic matter of one crystal- 
bearing plant, which proved to have the above composition, and 
in drawing their conclusions they considered that all crystals of 
apparently the same crystalline form, were of the same composi- 
tion. But it is difficult to tell, at all times, the exact crystalline 
form, as different forms sometimes resemble each other very 
much. And as the form may vary, so may the chemical compo- 
sition. Crystals of some form seem to be nearly or quite univer- 
sal; on close examination they may be found in some part Or 
parts of the majority of plants. In some plants they are only 
found in a certain position and of one form, while in others they 
may occupy several localities of the piant, and have as many 
forms. But the position and form often vary so much that it has 
been recommended by some authorities that they be made a 
family, and in some cases a generic distinction in the study of 
systematic botany. | 
rof. Geo. Gulliver, while making dissections under the micro- 
scope for the purpose of comparing the relations between the : 
structure of plants and animals, made note of every case, in the 
examination of plants where raphides or other crystals occurred, 
and he says: “It was not before a large accumulation of my 
notes had been examined that crystals were thought of in this 
point of view; for they had not even been particularly looked 
after, and were merely noted whenever seen, long before their | 
significance as characters were suspected. But when every one 
of these notes on raphides had been picked out, it was very Un- 
expectedly discovered that the plants in which they occurred 
would sometimes come under certain orderly arrangements. 
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