282 
surface of the leaf, they occur here only along the very edges ot 
the incurved margins. These long hairs project from either 
margin in such a way as to interlace along the whole length of 
the groove on the lower surface of the leaf. There is also a great 
increase in the number of the raised stomata. 
For the anatomy of the stem, sections were made in both 
species from shoots of one year’s growth. Again, beginning with 
a description of a/éa, a cross-section shows, in general, the struc- 
ture common to woody dicotyledonous stems of that age. Both 
species are alike in that there is no periderm formation the first 
year, but the epidermis remains until the formation of the second 
year’s wood. This is somewhat unusual, because in stems where 
a periderm is formed it is likely to appear very early in the first 
season. 
The epidermis, in the a/éa stem, consists of cells of ordinary 
size with the outer wall thickened and cutinized and the thicken- 
ing extending into the radial walls. Next to the epidermis is the 
zone of cortical parenchyma, which varies in depth from two t? 
several layers of large cells. Separating the cortical tissue from 
the central cylinder is a distinct layer of cells one layer in width. 
These cells have a longitudinal diameter about four times that of 
the radial and tangential, and their outer tangential walls Mea 
much thickened. Their walls also respond to the test for suberin, 
and they correspond to the endodermis sheath which DeBary de- 
scribes as occurring in the stems of some woody dicotyledons- 
The phloem zone is narrow and, like the phloem of the leaf bun- 
dle, is peculiar in having no bast elements. The cambium zone 
is about two rows of cells in depth. The libriform cells have bots 
dered pores in abundance on both their tangential and radial 
walls, but no simple pores. The ducts are numerous but not of 
unusual diameter for wood of this character, and they too have 
bordered pores and a few have spiral markings. Towards the 
pith are crowded the narrow tracheids which show both ring and 
spiral sculpturing. The medullary rays are one cell in width, and 
_ the pith cells are of the ordinary type. : 
Sections of the Conradii stem show a structure similar to that 
of alba. Its deviations from the typical dicotyledonous woody : 
stem, like those of C. a/éa, are an endodermis sheath, an aia 
