169 
There seems to be no doubt but this behavior of the endosperm in 
Lilium candidum is a provision for increasing the absorbing surface of that 
tissue in the region of greater food supply. These cells of the endosperm 
may, therefore, be known as endosperm haustoria. 
A similar behavior of the epidermal cells in certain parts of the em- 
bryo, such as the colyledons, serving as special organs of absorption, is 
well known, and a few striking illustrations of the same are brought 
together by Haberlandt in his “Physiologische Pflanzenanatomie.” 
The narrowed end of the embryo-sac, which extends into the chalazal 
region in certain Compositae (Senecio), is doubtless associated with a like 
function. In Senecio, however, the antipodal cells not only persist but 
multiply, while in Lilium candidum these disappear early, and the space 
which they formerly occupied is soon filled by endosperm cells. 
THE Errect oF CENTRIFUGAL Force Upon THE CELL. By Davin M. Mortrirr. 
[Pub.in Annals of Botany, 1899.] 
ABSORPTION OF WATER BY DECORTICATED Stems. By G. E. RIpPuey. 
It is probably known to all students of botany that the sap in a plant 
rises chiefly through the wood-cells, and not through the cortex-cells. This 
can be easily demonstrated by securing two similar leafy shoots from a 
tree or bush. From one, remove all the cortex for about an inch above 
the cut end, and from the other the wood for about the same distance. 
Now place the two prepared ends in water, and observe the rate of wilting 
as shown by the turgescence of the foliage. In a few hours, if transpira- 
tion is rapid, the shoot from which the wood has been removed will begin 
to wilt, and after a time will lose all turgescence, while the decorticated 
one will appear almost as fresh as at first and will continue so for a con- 
siderable time. This proves that the wood-cells and not the cortex-cells 
supply the water to the shoot. 
Last spring, while performing this experiment in the laboratory of 
vegetable physiology at Purdue University, it was observed that the third 
unprepared shoot, used as a control on the other two, wilted much sooner 
than the decorticated one. This observation at once raised the question 
