14 BOTANICAL GAZETTE [ JANUARY 
ent flowering time, some of them even blooming in the winter, 
that is, in the dry season, and in consequence we may find flow- 
ers at almost all times of the year. In Lagoa Santa grows 
a water lily, Nymphea Amazonum, and if any plant could be 
expected to show continuous growth such a one in a tropical 
lake should do so, even though it were an annual, which it hardly 
is. But at the beginning of the dry season this plant disappears 
from the surface of the lake, and not until the rainy season has 
come, in October, do the leaves and afterward the flowers appear 
anew. The very same fact, though not so distinctly, we find in 
the case of other water plants that are decidedly perennial. 
The second type of vegetation I wish to speak of I have seen 
in Venezuela and in the Danish West Indian islands; it is the 
dry bushes or scrub. Hardly any vegetation can be more dis- 
agreeable and ugly than this scrub of brambles and _ thorns. 
Thorny cactus and agave plants, with grayish and brownish hairy — 
leaves, that in the dry season partly fall; everywhere a baking 
heat and dryness, in some places an immense number of gnats; 
such is, in short, this scrub which we in northern regions never 
saw the like of; only in the Mediterranean countries, in the 
so-called Maquis, do we find anything similar. 
In a most striking manner the scrub shows us how the 
physiognomy of the vegetation depends upon physical condi- 
tions. These bushes have to defend themselves against too q 
intense drought, heat, and light. The outer and inner construction 
of every species bears an impress of that. The grayish hairy 
coverings, especially remarkable in the species of Croton, that 
give the whole landscape such an ugly appearance, are, in the 
first place, an excellent defense against transpiration, and this 
defense may be further strengthened by the rolling up of the 
leaves. On many Croton bushes I saw how all the leaves that 
were in shade were flattened, while those that were exposed to 
the direct sunlight had in different degrees rolled themselves 
up, so that the under side, which is the more hairy one, curved 
outward. This defense against drought is not quite unknown to 
us, only we have to seek it among plants that live upon dry, 
Sie hae seen tone 
Bagh allie = Re aby AY cain Fi eae eta ee Ree te Wea Me fi ee 
