II2 The Botanical Gazette. [March, 
plants grow. They are largely inhabitants of stony, sunny 
places with but little earth for the penetration of their roots. 
They are, therefore, protected against excessive drought by 
a fibrous coating, consisting not only of the roots but also of 
the remaining fibers of the leaf-sheaths. The author has 
observed that this fibrous coat absorbs water very rapidly and 
in large quantities. It is also probable that the erect and 
more or less carinate leaves serve the same purpose, viz., for 
a centripetal absorption of water. The stem is thus protected 
against excessive evaporation rather than against the frequent 
fires of the campos 
The structure of the leaf shows several peculiarities. The 
author has studied this especially from sections of the median 
portion of the blade, since it was observed that there exist 
certain differences between the structure of the basal and the 
median portion of the same blade. Vellozia compacta, for 
instance, shows at the leaf-base a tissue which reminds one 
very much of the thin-walled, transparent tissue so character- 
istic of Graminee, Cyperacee, Juncacez, etc., while this 
tissue was not observed higher up on the same leaf. 
of the blade in a dry atmosphere. The stomata are arranged 
in longitudinal rows. Vedlozia has a distinct palisade-tissue, 
which is almost lacking in Barbacenia, and the structure thus 
becomes nearly isolateral. Inthe genus Barbacenia certain 
cells of the mesophyll were observed to contain water. Sim- 
ilar water-storing cells were also observed in Ved/ozia, but 
in this case they belonged to the hypoderm. 
There is a certain distinction between the development of 
the various tissues of the leaf not only within these genera, 
but also within their species. These differences appear to 
the author to be of value in the anatomical characterization 
of the species of the tribe. THEO. HOLM. 
Ombrophilous and ombrophobic organs of plants.’ 
Although this treatise on the adaptation of plants to ¢X- 
treme amounts of rain is only preliminary, it nevertheless 
Oe ea, 
tJ. Wiesner: Ueber ombrophile und ombrophobe Pflanzenorgane. Sitzungs~ 
berichte d. kais. Akad. d. Wissensch. Wien. 102: —.1893. 
