1880.) Microscopic Crystals contained in Plants. 779 
In Cynthia virginica raphides of small size but no inuline were 
found. There were also a few cubical crystals in the lower part 
of the stem and in the flower receptacle, which gave answer to 
the test for carbonic acid with acetic acid, but the raphides proved 
to be phosphate. The cubical crystals were about the goyoth of 
an inch in diameter. 
Senecio aureus and S. balsamite contained acicular crystals 
which, upon chemical examination, gave evidence of oxalate of © 
lime. In this genus I was not able to find any raphides at all, 
nor any inuline. A few crystals were present, but on account of 
their small size and number, I was neither able to determine their 
form nor chemical nature. 
Lappa major, or common burdock, contained in the flower 
receptacle and dried fruit, minute cubical crystals, which gave the 
tests for carbonate of lime. No raphides or acicular crystals of 
any sort were present. 
Tanacetum vulgare contained both cubical and kient crystals, 
the latter in the leaves and petiole, and the former in the flower 
parts; and upper part of the stem ; both oxalate and carbonate of 
‘lime seemed to be present. 
The raphides of this order seem to be rarer in the division 
or sub-order Ligulifloree, while the acicular crystals or crystal 
prisms were only found in the sub-order Tubuliflore. Inuline is 
common to both sub-orders. 
It will be seen on reference to my work that the raphides 
seemed to be composed of phosphate of lime, the acicular or 
crystal prisms, of oxalate, and the cubical crystals, of carbonate of — 2 n 
the same, while the sphæraphides seemed to be the same base 
combined with different acids according to their locality. 
It will be remembered that in the first part of this paper I 
mentioned the fact that crystals of some form were nearly if not | 
quite universal, and as some slight evidence of this I have com- Le 
piled with care a list of all the families in which crystals have 
been reported. This is the beginning of a more complete list of 
the genera and species which I hope soon to have ready for pub- — : 
lication, which will be classified according to the mee of oe 
Crystals that the species may contain. 
1A variety of S, aureus. 
