92 Hill .— 77 ^ Structure and Development of 
a branch from 7, but to arise independently h It seems very 
probable that this may be a special anomalous case, as in 
other respects the behaviour of the bundles is similar on the 
two sides of the leaf; so that one would expect a branch from 
7 to occupy the position filled in this particular leaf by the 
bundle e . 
There is a certain amount of variation as to the course of 
the bundles in different leaves ; for example, it was found that 
in another leaf the bundle corresponding to 1 gave off a branch, 
which finally occupied a position similar to that of 9 in the 
leaf described above. Then, again, the adjacent bundles of 
some leaves, especially the larger ones, anastomose somewhat 
freely in the transitional regions between the sheath and the 
blade. The main points, however, expressed above are typical. 
The structure of the assimilatory region of the leaf is illus¬ 
trated in Fig. 8. The epidermis is well marked and, in 
the older parts of the leaf, is covered with a cuticle of fair 
thickness. This cuticle, like that of the flowering stem, is 
longitudinally ridged, there being from three to five ridges to 
each epidermal cell. The stomata are numerous, showing a 
typical structure, and are placed slightly below the general 
level of the epidermis. The palisade-parenchyma is several 
layers in thickness, and is made up of oval-shaped cells with 
small air-spaces between them. 
Glandular bodies are developed in the axils of the leaves ; 
in shape they are triangular and flattened, and very frequently 
quite numerous, as many as seventeen having been counted 
in one leaf-axil: they are sessile and made up of parenchy¬ 
matous cells, with dense contents and well-marked nuclei, 
somewhat larger than are found in the non-glandular vege¬ 
tative parts of the plant. 
Xrmisch (10) was the first to call attention to these glands 
in the leaf-axils of Triglochin maritimum . 
1 No definite connexions were to be made out^between^these and the adjacent 
bundles; this may be due to the fact that the leaf was quite a young one, and still 
retained its merismatic condition. It might also be noted that these bundles, b } 
and c, are not found in all leaves. 
