1886.] Variation of Water in Trees and Shrubs. 433 
PERIODS FOR CESSATION OF GROWTH. 
As upon theoretical grounds the tissues contain most water 
when the growth is most active, data which will enable us to 
accurately fix the limiting periods for the season’s growth, will 
have an important bearing upon this question. Mr. W. E. Stone, 
accepting the completion of terminal buds as marking comple- 
tion of the longitudinal growth for the entire year, has obtained 
the following data as establishing the limiting periods of growth 
for the latitude of West Point, N. Y., 41° 23° N.: 
JUNE IST. 
Acer saccharinum Wang. Quercus alba L. 
“ rubrum L, “ bicolor Willd. 
Amelanchier canadensis Torr. & Gray. e coccinea Wang. £ 
Carya alba Nutt. “ rinus v- monticola Michx. 
Fagus ferruginea Ait. \ Sambucus pubens Michx. / 
raxinns americana L, Tilia americana L, 
Hamamelis virginica L, Ulmus americana L. 
Kalmia latifolia L. “« fulva Michx, 
Populus tremuloides Michx. 
JUNE I5TH. 
Betula lenta L. Lindera benzoin Meissn. 
Carpinus americana Michx. Morus rubra L. 
Castanea vesca L, Ostrya virginica Willd. 
Juglans nigra L. Prunus cerasus L. : 
JULY IQTH. 
Andromeda ligustrina Muhl. Nyssa multiflora Wang. 
Alnus incana Willd, Staphylea trifolia L. 
INDETERMINATE PERIOD, 
Ampelopsis quinguifolia Michx, Rhus sp.— ; 
Celastrus scandens S Vitis sp.— 
Growth in length having ceased at these periods, the energy 
of the plant then becomes directed to the lignification of o 
tissues and the deposition of reserve material for growth the 
following year. These changes, however, of necessity involve 
a continual decrease in the contained water. The data above also 
show that the majority of plants complete their longitudinal 
Stowth within the first six weeks of the growing season; that 
Most of these complete their growth in from three to four weeks; 
an as the season advances, the number of plants still grow- 
‘NS, rapidly diminishes until the middle of July, after which time 
> are left but few, those being plants like the grape, which- 
continue to grow until arrested by severe cold. A 
Bull. Torrey Bot, Club, xit, 8, 83. 
