OF AMMONIA ON THE ROOTS OF PLANTS, 253 
over many, but by no means all, of the elongated cells surround- 
ing the vascular bundle included dark-brown fine granular matter. 
Three roots which had been left in water for the same length of 
time, viz. 207 hours, were similarly examined, but their cells pre- 
sented none of the above appearances. 
Primula acaulis.—Several roots were left (Dec. 22) for 18 hours 
in a solution of 4 to 1000, and they were all much affected, except 
some of the thinnest rootlets. Many of the exterior cells con- 
tained granules within the shrunken protoplasmie utricle, which 
had contracted into one, two, or even three, oval or spherical 
bags, lying within the same cell. The rows of cells containing 
the granules showed some tendency to alternate with rows of 
empty cells. The granules were rendered orange-brown by iodine. 
The innumerable root-hairs all arose' from the empty cells ; and 
Isaw only two partial exceptions, in which the outer walls of 
cells containing granules were produced into short papille, as in 
the formerly deseribed case of PAyllanthus, and these resembled 
nascent root-hairs. Within one of these papille, granules sur- 
rounded by the shrunken utricle could be seen. In the paren- 
chyma single cells were seen containing minute hyaline globules, 
which were colourless or pale or dark blue, or occasionally 
greenish or yellowish. Many of the endoderm-celis lıkewise 
contained more or less confluent hyaline globules; but these were 
colourless, and larger than those in the parenchyma. They 
resembled starch-grains so closely that they were tried with 
iodine, but were not coloured blue. Roots which had been kept 
for 48 hours in water exhibited none of the coloured or colourless 
globules; but these appeared when the roots were afterwards 
immersed for 24 hours in the ammonia solution. 
Although it is certain that granules were deposited in the 
exterior cells in the case just-described, yet in four other roots, 
after an immersion of 24 hours in the solution, no granules could 
be seen in any of the exterior cells. Some of the parenchyma- 
cells, however, were of a fine blue colour, and contained many 
globules or granules, but no starch-grains, while others contained 
starch-grains as well as some few globules. 
Cyclamen persicum.—Sections taken from roots of this plant 
which had been immersed in a solution of carbonate of ammonia 
presented an extraordinary different appearance from those of fresh 
roots. All the cells in the latter appeared empty, excepting those 
of the endoderm, which sometimes included a few very fine pale- 
