On Laticiferous Tissue in the pith of Manihot 
Glaziovii, and on the presence of Nuclei in 
this Tissue. 
BY 
AGNES CALVERT 
AND 
L. A. BOODLE, A.N.S.S. 
With Plate V. 
I. 
I N April 1884 Dr. D. H. Scott published the results of his 
investigations on the Laticiferous Tissue of Manihot 
Glaziovii 1 , showing that in this plant the laticiferous tubes, 
unlike those of the Euphorbiaceae previously investigated 2 , 
are formed by the fusion of rows of cells, The two systems 
of laticiferous vessels, already distinguished by Trimen, were 
described, one being derived from the hypodermal layers of 
the external cortex, while the other is developed in the 
phloem. 
In repeating some of these investigations, under Dr. Scott’s 
superintendence, we found a third system, which occurs in the 
pith. 
Transverse sections through internodes where secondary 
thickening has made some progress show that the peripheral 
part of the pith has thinner walls and contains more abundant 
starch and other cell-contents than the rest of the pith. It is 
1 Quart. Journ. Microscop. Science, vol. xxiv. pp. 194-204. 
2 Cf. De Bary, Comp. Anat. of Phanerog. and Ferns, Eng. ed., p. 437. 
Annals of Botany. Vol. I. No. I. August 1887.] 
