268 BOTANICAL GAZETTE [MARCH 
to 55° C. the toxic properties seem to have been destroyed, which together with 
other data leads to the conclusion that the substance acting as a fungicide is 
an enzyme. It serves to explain the fact that no endophytic fungi are found 
in the bulbous portions of various orchids, although they are always present in 
the roots of the same plants, thus conforming to BERNARD’s hypothesis that 
these orchids are plants which tolerate the mycorhiza, while at the same time 
they are able to defend themselves against their complete invasion. These 
investigations were still in progress when they were interrupted by the death 
of the brilliant scientist who has contributed so largely to the understanding 
of the symbiosis existing between various endophytic fungi and their hosts.— 
Gro. D. FULLER. 
Vegetation of islands and peninsulas.—From a brief study of the 
irregular shore line of Lake Tsala Apopka, Florida, and an examination of the 
literature on the vegetation of the Atlantic coastal plain, HARPER?’ finds that 
the peninsulas and islands are almost universally characterized by a vegetation 
of a climax type composed largely of broad-leaved evergreen trees, —- 
which Magnolia renditions and Quercus spp. are conspicuous. This 
striking contrast with the pine forests which occupy the adjacent inland: 
Several possible hypotheses in explanation of this phenomenon are examined 
and rejected, as fire seems to the investigator to afford an adequate key to the 
situation. Fires would doubtless be of much less frequent occurrence upon 
islands and peninsulas than upon the more continuous mainland, and this 
circumstance would permit a more rapid advance toward mesophytism, but it 
seems possible that differences of soil moisture and evaporation due to the 
proximity of considerable bodies of water and to the slight elevation of the 
islands and peninsulas above their surface may have been at least secondary 
factors in hastening the development of the climax vegetation.—Gro. D 
Phylogeny of algae.—BrUNTHALER™ has discussed the phylogeny of 
gae 
obtained by ENGELMANN, OLTMANNS, STAHL, Piitrer, and others. A brief 
summary of his conclusions is as follows: (1) The chromophyll and chlorophyll 
of Rhodophyceae, Phaeophyceae, Zygophytae (including Peridinales, Bacil- 
lariales, and Conjugales), are the result of adaptation to light intensity since 
these forms first appeared. (2) The modern Flagellatae are end structures 
from the oldest organisms, but the direct relationship of the modern flagellates 
with these ancient organisms cannot be demonstrated. (3) The Rhodophy- 
ceae are to be regarded as phylogenetically the oldest group of algae, and their 
ancestors have come from the primitive forms of flagellates. (4) The Phaeo- 
27 HARPER, ROLAND M.., The relation of climax vegetation to islands and penin- 
sulas. Bull. Torr. Bot. Club 38:515-525. 1911 
28 BRUNTHALER, JosEeF, Zur Phylogenie der Algae. Biol. Centralbl. 31: 225-230. 
Igil. 
