134 DR. F. E. FRITSCH ON THE 
undulate ; in transverse section they are more or less quadrate, or somewhat elongated in 
the plane of the leaf. The lower epidermal cells are smaller than those of the upper side, 
but generally have the same shape, although somewhat flatter in transverse section. 
In certain specimens of Juliania adstringens (Rose and Hay, 5341) the upper epidermal 
cells in a transverse section show slight elongation in a direction at right angles to the 
surface of the leaf, 7. e., they are rectangular in shape; as a consequence, the surface- 
view of the epidermis shows rather smaller cells than in the other cases. This peculiar 
shape is probably related to some special condition of the habitat, which it is at present 
impossible to define: this is not the only peculiarity exhibited by the leaf in these 
specimens of J. adstringens (cf. below). Returning to the general characters of the 
epidermal cells, it may be noted that they are not very strongly thickened ; the lateral 
walls are thin and the outer walls only slightly thickened (except in J. amplifolia and 
J. mollis). The latter are often slightly arched outwards, especially near the veins. 
There is a well-marked cuticle, which in most cases is very distinctly striated (not shown 
in figs.); it is smooth, however, in Orthopterygium. Huaucui. Yn Juliana glauca the 
marking of the cuticle amounts almost to the formation of cuticular ridges having a very 
irregular course ; on the lower epidermis these cuticular ridges project to some extent 
over the guard-cells of the stomata, forming a kind of fringe around them. The cuticle 
often exhibits a tendency to split away from the rest of the section, this being specially 
noticeable in J. glauca. 
The stomata (fig. 1, A, B, D) are relatively large, being about 30 » in length; in 
surface view they are often rather elongated. "There are no subsidiary cells. The 
mother-cell of the guard-cells in J. mollis is cut off by the first division-wall, and this is 
probably true of all the members of the Order. The stomata are frequently raised 
a little above the level of the surrounding epidermal cells ; they are contined to the 
lower epidermis, except in J. adstringens, in which scattered stomata are occasionally 
found on the upper side of the leaf as well (Nelson, 1827). 
The most prominent feature of the epidermis is its a ppendages (fig. 1); long multi- 
cellular clothing-hairs and small, delicate, glanduiar hairs are found on both surfaces of 
the leaf, although generally more abundant on the lower. They constitute a plentiful 
hairy covering in all but Juliania glauca, in which the clothing-hairs are only of isolated 
occurrence. The clothing-hairs (fig. 1, A, C, D) are entirely unbranched and as a 
rule multicellular, consisting of from two to many cells; hairs composed of a large number 
(10 or more) of cells are particularly characteristic of J. mollis, whilst smaller numbers 
(4 or 5) of cells form the trichomes of J. adstringens and J. amplifolia (fig. 1, C). In 
Orthopterygium Huaucui (fig. 1, D) the hairs for the most part consist of two cells only 
and frequently show a further reduction to the unicellular condition; unicellular hairs 
also occurred quite commonly amongst the multicellular ones in some specimens of 
Juliania adstringens (Rose and Hay, 5341). The hairs either stand out stiffly from the 
epidermis (fig. 1, A) or are curved in various ways (fig. 1, C, D). The former type is 
found in J. amplifolia and J. mollis ; they have long hairs tapering very gradually toa 
point and often slightly curved at the apex (fig. 1, A); the lateral walls of these trichomes 
are thick and surround a well-marked lumen, which is divided up into a number of 
