78 BOTANICAL GAZETTE [JULY 
accepted as the best expression of the conditions which affect the water rela- 
tions of plants. Unfortunately, the soil moisture data are too scanty to afford 
a good basis for comparison, and are not expressed in terms indicating what 
proportion of this moisture is available for plant production. The temperature 
control has been experimentally studied for a few species, and the results have 
been previously reported.4 These are given some further consideration, while 
slope exposure and topographic relief are carefully discussed. Perhaps nothing 
shows the unusual character of the factors controlling vegetation more than 
the fact that succession due to physiographic development and to the reaction 
of the plant upon its habitat is almost completely absent. 
In its efforts to determine in a quantitative manner the climatic and other 
physical factors involved, and in its careful attempts to correlate these factors 
with vegetation, this report may be regarded as an excellent example of modern 
ecological investigation. The illustrations are numerous, well chosen, and 
reproduced in the excellent manner that has usually characterized the publica- 
tions of the Carnegie Institution, while the organization of the material pre- 
sented is decidedly better than that of many similar publications that have 
come to the attention of the reviewer.—GEo. D. FULLER 
Vegetation and tide levels—The excellent opportunities for investigating 
the problems of seashore vegetation at Cold Spring Harbor, New York, afforded 
by the location at that place of the Biological Laboratory of the Brooklyn 
Institute of Arts and Sciences and the Carnegie Station for Experimental 
Evolution has been appreciated by many botanists, and the factors determin- 
ing the composition and distribution of the various plant associations in the 
vicinity are becoming better known. In 1912 JOHNSON and YorK5 made a 
preliminary announcement of the results of a survey of the inner harbor, and 
indicated the relations of the various plant associations to tide levels. This 
was followed by a more general paper by TRANSEAU® on the littoral successions 
of the vicinity, devoted principally to a consideration of the lines of succession 
followed by the seed plant communities from the salt marsh to the pine barrens. 
More recently there has come the full report of the careful survey of JOHNSON 
and York,’ who have confined their attention to the vegetation of the inner 
harbor. 
4 SHREVE, Forrest, Influence of low Lenonen on the distribution of the 
giant cactus. Plant World 14:136-146. 1 
, The réle of winter buaseiacGiee in : determining $3 distribution of plants. 
Amer. — Bot. 1:193-202. 1914; see review in Bort. Gaz. 59:502-503. I9QIS. 
5 Jonson, D.5S., and York, H. se day relation of plants to tide levels. Johns 
: ~— Univ. Circulas no. 2. pp. 6. 
u, E. N., The stake ee Cold Spring gt Long Island. I. The 
littoral succession. Plant World 16:189-210. figs. 1-8. 
7 Jounson, D. S. and Yorx, H. H., The relation of gone to tide levels. Car- 
negie Inst. Wash. Publ. no. 206. pp. 6a, pls. 24. figs. 5. 1915. 
