545 
Reed.—On the Anatomy of some Tubers. 
A few remarks might conveniently be added at this point with refer¬ 
ence to the distribution of inulin in these tubers and its influence on cell 
division. The inulin is seen in young tubers as masses of sphere crystals 
surrounding the xylem elements of the bundles and ‘ welling ’ over into the 
immediately adjacent parenchyma. Tuberization does not appear to com¬ 
mence until these crystals are deposited in the young tuber, but as soon as 
Diagram IV. Ph., ploem. xy., xylem. P. xy., protoxylem. M. pith. xy. par., xylem 
parenchyma. 
they appear divisions commence in the parenchyma in their immediate 
vicinity. In some few cases the distribution of the inulin crystals was 
irregular; one side of the young tuber might contain an abundance of 
inulin, whilst the other side had comparatively little. When such was 
found to be the case the region devoid of inulin deposits had not become 
meristematic. It would appear then that the presence of the food reserve 
has a stimulating effect on the cells in which it is deposited, or it may 
possibly be the reverse, i. e. the activity of the cells demands a supply of food 
material. 
From the above it is seen that the tuber of Helianthus tuberosus is made 
up of parenchyma derived from the activity of the medullary tissue and 
