23G 
suleae from Mesembryaceae — and here, too, this diagnosis 
holds good, from the very cradle to the grave of the species. 
Experiments to this end may be easily repeated on old or 
dead plants and on seedlings of the many Mesembryan- 
themums and Sedums grown in pots ; and when together in 
the same pot, the evidence will be quite conclusive that the 
raphides are produced in one of the two plants, and not in 
the other, though both are under the very same conditions of 
soil and climate ; in fact, all my experiments and observa- 
tions are to the effect that no raphis-bearing species can 
grow and flourish without producing raphides, while the 
raphidian organism cannot be formed under any circumstances 
in other plants. 
Of our Exogenous trees and shrubs, I know not a single 
raphis-bearer, though other crystals are common in their 
plants generally, and raphides are found in many exotic 
trees and shrubs of this class ; facts thus far noteworthy and 
deserving of further inquiry. Boih raphides and sphaera- 
phides are plentiful in Vitaceae, of which either the Grape 
Vine or American Creeper may be had at any time for 
examination, though the leaves, young shoots, ovaries, and 
ripe fruit are in some respects best for the purpose. 
Our Dictyogens abound in raphides, as may be well seen 
in the Black Briony and Herb Paris ; and so does the Trillium 
of the gardens. Of Tamus the raphides appear loose and 
destitute of a cell in the ripe berry-pulp, and in the root- 
stock; this root is like a little Yam, and the officinal Yams, 
so commonly used as food in the \Yest Indies, and the New 
Chinese Yam ( Dioscorca Batatas), of late years vainly ad- 
vertised and cultivated as a substitute for the potato in 
England, are both also Dictyogens affording raphides. At 
Covent Garden different things are exposed for sale, as Yams, 
one of which belongs to the exraphidian order Convolvulacese. 
In Paris quadrifolia the raphis-cells are elongated, pointed 
at the ends, and much larger than the contained raphides, as 
may be well seen through the tissues of the perianth-seg- 
ments. Both this and Tamus are good plants for these 
examinations ; and in some districts, as the clayey parts of 
Kent, the scarlet berries of the Black Briony adorn the 
hedges during the autumnal and winter months. A botani- 
cal friend was so much disappointed at not finding raphides 
in “ some scarlet berries of Briony” that he produced the 
fruit for my correction ; but it soon appeared that he had 
only got the Red Briony, a plant of the Exogenous order 
Cucurbitaceae, and which I have always described as ex- 
raphidian. He might as well have searched for raphides in 
