390 
Notes. 
longitudinal divisions already mentioned (the figures will make the 
arrangement plain). The cells composing the outer of the two 
innermost layers behave, as regards their mode of cell-multiplication, 
in precisely the same way as those of the layer just described, with 
the difference that the plane of division is parallel with the long 
axis of the bud. The result of this is, that in a transverse section 
the cells of the inner layer which lie in the plane of the section 
( ilc d 
Fig. 21. 
Fig. 2 2 . 
Endocarp of Sambucus nigra. Fig. 21, Tiansverse section from young bud. 
Fig. 22, Longitudinal section of a somewhat older stage, a , b, c, The layers forming 
the endocarp. d, Innermost layer of pulpy tissue. 
appear as a segmented ring-like cylinder, whilst those of th e 
outer layer resemble a circular chain, the links of which represent 
the cut ends of the cells whose greatest diameter is parallel with the 
long axis of the flower. In a longitudinal section this arrangement 
must evidently be entirely reversed (compare figures 21 and 22). 
As development goes on, and as the bud increases in size, the 
primitive walls, which cut the cylindrical rings into segments, undergo 
a change of position becoming more and more oblique ; and whilst 
the circular or elliptical form of the band as a whole remains un- 
altered, the individual cells composing it suffer a change of shape 
and are finally converted into elements with long pointed ends, the 
pointed portions slipping over each other in such a way that the 
thickness of the whole ring remains for a time fairly constant 
throughout. As a consequence of this, sections transverse to the 
