238 Rhodora [DEcEMBER 
it closely through a lens and soon observed minute droplets of solution 
appearing at intervals along the grooves. I held a portion of the leaf, 
upon which were several droplets, tightly upon my finger and noticed 
that the heat of my finger caused a little water to evaporate and that a 
cubical crystal formed, which was nearly as large as the droplet had 
been. I repeated this operation some twenty times, and found out 
how it was that some of the crystals were upon the carinae, for when 
a large drop evaporated it did not form a single large crystal, but 
formed four small ones, two of which were deposited upon the top of 
each ridge which bordered upon the groove. 
Next I brought three entire plants to the Laboratory, cleaned one 
thoroughly of all crystals, and placed their roots in sea water. ‘The 
next three days were foggy and the droplets excreted by the specimen 
which I had cleaned off remained as such, while the crystals on the 
other two specimens deliquesced. But on the fourth day the weather 
was dry and crystals appeared abundantly on all three plants. 
I again cleaned off a leaf of the plant from which I had previously 
removed the crystals, and placing it over my finger watched the droplets 
emerge and the crystals form. 
I then tested some of the juice of the leaf with AgNO, and got a 
heavy white precipitate which was insoluble in HNO,, thus showing 
an abundance of chlorides. ‘The solution excreted by the leaf gave an 
even heavier precipitate. Further than this very rough analysis I was 
unable, on account of lack of reagents, to carry my chemical investiga- 
tions. 
Some portions of leaves I fixed in chromo-acetic solution, brought 
them to our Botanical Laboratory, imbedded in paraffin and made 
sections in three planes to see if water-pores were present. I found 
that they were not, but that stomata were abundant and had very large 
intercellular spaces beneath them. ‘The stomata are situated mostly 
near the bottom of the grooves. ‘The grooves are very deep and have 
numerous small epidermal projections upon their walls. 
BOTANICAL DEPARTMENT, 
Queen's University, Kingston, Canada. 
