381 
correctness of his assumptions. While examining root tubercles 
of Cycas revoluta | noticcd that the palisade layer cells contained 
many rather large cytoplasmic granules (dermatosomen, zell 
granula, elementarorganismen, etc.). They are highly refractive, 
spherical in shape, and in size varying, beginning at the limits of 
of observation to one half mikron (“) in diameter; a few are as 
much as one “ in diameter. Only the larger ones were noticeable 
with the objectives at my disposal (Zeiss 2.0 mm. hom. imm. 
ap. 140). On the addition of aqueous cor. sub. solution (71, per 
cent.) they took on a dark stain and were brought to view very 
much better. It was seen that the protoplasm was made up of 
granules of all sizes up to the limit given. Most of the aniline 
dyes stain them more or less. To my knowledge nothing is 
superior to the above mentioned sublimate solution. In the case 
of Cycas root tubercles it seems to answer much better than Alt- 
mann’s method, which consists in adding alcoholic sublimate solu- 
tion followed by acid fuchsin stain. The fact that I noticed quitea 
number of hourglass forms led me to suppose that they underwent 
division, though Wiesner states that they probably have lost the 
Power to do so. I made some culture experiments, not with the 
€xpectation of developing a culture of plasomen, but rather, if pos- 
sible, to study their vitality outside of the cell. .Cycad tubercles 
were carefully washed, then dried quickly by means of blotting 
Paper which had been passed through the flame of a Bunsen 
_ burner; then the tubercle itself was passed through the flame so 
as to singe it on all sides. With a sterilized knife the dermal 
layer was cut down one side and the tubercle broken (not cut) 
across. The inoculations were then made from the green pali- 
Sade layer upon various agar-veg. extract media. The inoculated 
tubes were then placed in a dark incubator at a constant tempera- 
ture of 35° C. After from three to five days a small growth was 
Noticed in most tubes at points of inoculation. Examination 
Showed the presence of cocci and bacteria. Treating with 
aqueous sub. sol. showed also the presence of plasomen. These 
Were introduced with the inoculating needle and became more or 
less intermixed with the cocci and bacteria culture. I made re- 
peated examinations of these cultures at intervals of several days, 
always finding a few plasomen. After a period of three or four 
