1921] CURRENT LITERATURE 245 
are adsorbed by the clay and humus, and the acids set free. In such areas 
the reaction is often found to change sharply within a few centimeters from 
a specific alkalinity of 30 to a specific acidity of 300. These methods and 
results seem likely to place the old contention of the relative importance of 
the physical and chemical properties of soil upon a new experimental basis, 
and to result in a much clearer conception of the meaning and application 
of the terms “oxylophytes” and “calcicoles.”—Gro. D. FULLER. 
Seacoast vegetation.—A description of the vegetation of the eroding sea- 
shores of Connecticut has been added by NicHors* to his other studies of the 
vegetation of the state previously noted in this journal.27 He groups the 
important factors as those relating to submergence, such as salinity, tides 
illumination, and temperature of the water, those relating to physionrapky, 
distinctive associations are described. The range of the studies is from the 
sublittoral algal associations to the forests which fringe the shores. 
The depositing shores present even more diverse conditions,* depending 
principally upon the character of the soil, stony, sandy, and muddy areas, 
each having characteristic series of associations. The various associations 
are carefully described, and in the actual succession along muddy shores there 
is found evidence of coastal subsidence similar to that presented by GANONG, 
PENHALLOW, BARTLETT, and o 
Some attention is devoted to the salt marsh depressions or “pans” which 
appear to have various origins. Some are due to the destruction of the 
ordinary salt marsh vegetation by the decay of masses of plant remains swept 
over the surface during times of unusually high water, but others result from 
the partial filling and obstructing of tidal creeks and lagoons or by the building 
of tidal levees and the consequent ponding of water, between tides, in the 
lower parts of the marsh.—Gro. D. FULLER. 
Crown gall of alfalfa.—W1tson” has described and figured in some detail 
the fungus causing crown gall of alfalfa. He concludes that the parasite is 
present in the gall in the form of a plasmodium, formed by the fusion of amoe- 
boid cells in the host cells. He thinks that it spreads through the host tissues 
as a streaming mass or network of naked protoplasm, and that any mycelium 
observed has no connection with the gall forming organism. This plasmodial 
% Nicuots, Gro. E., The vegetation of Connecticut. VI. The plant associations 
of eroding areas along the seacoast. Bull. Torr. Bot. Club 47:89-117. fig. 6. 1920. 
, Bor. Gaz. 59:159-160. 1915; 652572. 1918. 
——, The vegetation of Connecticut. VII. The associations of depositing 
areas along pret seacoast. Bull. Torr. Bot. Club 47:511~548. fig. 10. 1920. 
*9 Bor. Gaz. 70:51. 1920. 
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