1907] ‘ CURRENT LITERATURE 353 
tions of the fruit-bodies and mycelia of the fungi considered. The author attempts 
to distinguish form-types of perithecia according to their position on or their relation 
to the elements of the stem; for example, the perithecia originating under 
sclerenchyma sheath are flattened, while those originating under the epidermis 
are round. That pressure from any cause will influence the form of perithecia 
is self-evident and of little importance. One general fact to be deduced from the 
paper is that the sclerenchyma tissue is not penetrated by the fungous hyphae. 
The second paper, by Duysen,?° deals with wood-inhabiting discomycetes. 
In this it is shown that the mycelium of many of these fungi, as Helotium, Coryne, 
Mollisia, and others, penetrates the cells only by the pits or by cracks and fissures 
caused by other agencies. Enzyme action here is apparently of less importance 
in aiding the hyphae to penetrate cell walls. _ In others, like Propolis and Schiz- 
oxylon, more or less of the wood is actually destroyed by enzymosis, mostly in 
the vicinity of the fruit-body. The sclerenchymatous tissue is not injured—H. 
HASSELBRING. 
A study in endemism.—Mount Ritigala is an isolated mountain in north- 
central Ceylon, within 100 feet of whose summit there occurs a remarkable flora, 
covering only a few acres. In this small space there exist species that belong to 
the flora of the wetter districts of Ceylon, a regular oasis of vegetation distinct 
from the dry country surrounding it. Wrruts?? has studied the possibilities 
of the origin of this isolated flora and its endemic forms. The number of species 
enumerated is 144, but 41 of these are eliminated as occurring also in the dry 
zone and so are not compelled to travel 40 miles to reach the summit. The 103 
remaining species all belong to the moist region of Ceylon, at least 40 miles away. 
Of these species, 24 can be carried by birds, 49 by the wind, and the distribution 
methods of the remaining 30 are doubtful. After various analyses of the statis- 
tics, the conclusion is reached “that endemism, other things being equal, goes 
in general with difficulty of distribution, and with rare arrival in one spot.” For 
example, the bird-carried forms arrive more regularly than the others, and there 
is one endemic form among the 24 species; the wind-carried forms arrive less 
regularly, and there are three endemic forms among the 49 species; while the 
plants whose method of distribution is called “doubtful” arrive most rarely, 
and there are 8 endemic forms out of 24 species, 6 of the 30 species being rejected 
for a special reason.—J. M. C 
Motor mechanism of Berberis stamens.—JUEL?? has made some interesting 
observations and experiments on the staminal filaments of Berberis and Cen- 
° Duy: FRANZ , Ueber die Beziehungen der Mycelien einiger, haupt- 
stichticn aparece ere i g ereineelenens zu ihrem Substrat. Hedwigia 46:25-56: 
figs. 7. 1906. 
2x Wirzis, J. C., The flora of Ritigala, an isolated mountain in the north-cen 
Province of Ceylon; a study in endemism. Annals Roy. Bot. Gard. Peradeniya 
3:271-302. 1906. 
22 JuEL, H. O., Einige Beobachtungen an reizbaren Staubfaden. 
tillagn. F. R. KyELLMAN 1-20. 1. 1. Upsala. 1906. 
tral 
Bot. Stud. 
