24 Life and Immortality. 
lobes begin to separate as soon as the contraction of the 
upper surface diminishes, 
Six known genera, Drosophyllum, Roridula, Byblis, 
Drosera, Dionza and Aldrovanda comprise the Droseracex, 
all of which capture insects. The first three genera effect 
this purpose solely by the viscid fluid secreted from their 
glands, and the last, like Dionzea, which has already been 
described, through the closing of the blades of the leaf. In 
these last two genera rapid movement makes up for the 
loss of viscid secretion. But of all the genera none is more 
interesting than the typical Sundews. 
Growing in poor peaty soil, and sometimes along the 
borders of ponds where nothing else can grow, certain low 
herbaceous plants, called Droseras, abound. So small and 
apparently insignificant are they, that to the ordinary observer 
they are almost unnoticed. But they have peculiarities of 
structure and nature that readily distinguish them. Scattered ° 
thickly over their leaves are reddish bristles or tentacles, each 
surmounted by a gland, from which an extremely viscid fluid, 
sparkling in the sunlight like dew, exudes in transparent 
drops. Hence the common name of Sundew by which the 
half-dozen species found in the United States east of the 
Mississippi River are known. A one-sided raceme, whose 
flowers open only when the sun shines, crowns a smooth 
scape, which is devoid of tentacles. Drosera rotundifolia, 
our commonest species, has a wide range, being indigenous 
to both Europe and America. In the United States it extends 
from New England to Florida and westward, and is occa- 
sionally associated with Drosera longifolia, a form with long 
strap-shaped leaves, but whose distribution is mostly restricted 
to maritime regions, from Massachusetts to Florida. 
All of the species are remarkably similar in habits, captur- 
ing insects, and digesting and absorbing the soft parts, a 
circumstance which explains how these plants can flourish 
in an extremely poor soil where mosses, which depend 
almost entirely upon the atmosphere for their nourishment, 
