64 MISSOURI BOTANICAL GARDEN BULLETIN 
the center of the leaf as well as bringing more secreting 
glands in contact with it. Besides small insects, spores, 
pollen-grains, and other plant substances brought by the wind 
not infrequently fall on the viscid surface of the leaf, are 
digested, and the soluble portions are absorbed. 
Drosera, the sundew, of which almost forty species are 
known, thrives in practically the same regions as the butter- 
wort, and emai the two are found growing in the same 
area. That which impresses one most at first sight of this 
plant is the presence of the delicate bristles, on the upper 
surface and margin of the leaf, each bristle surmounted by 
a tiny drop of fluid, which sparkles in the sunlight like a 
drop of dew, whence the name “sundew.” At the extremity 
of each bristle is a gland which secretes this clear, sticky 
matter whose function is essentially the same as that of the 
glands on the leaf of the butterwort. When a small insect 
alights on the leaf and touches the glands there ensues an 
increase in the discharge of fluid, which now is acid and 
contains in addition a protein digesting enzyme, or ferment. 
The insect is caught by the sticky juice, and in trying to 
iberate itself, becomes hannearad with the secretion, the 
latter greatly impeding its movements. The breathing 
organs are soon covered, and after a brief interval, during 
which all efforts on the part of the captive to escape cease, 
the insect dies of suffocation. All these phenomena corre- 
7 es in the main, to those occasioned by similar causes in 
e case of the butterwort. The leaves of the sundew, how- 
ever, are especially characterized by the movements of the 
tentacle-like bristles in response to a stimulus by animal 
matter. When an insect becomes secured by the mucilagin- 
ous glands, a stimulus is conveyed to the nearest neighbor- 
ing tentacles, and gradually to those farther away, with the 
result that the tentacles, in regular order, begin to bend in- 
ward toward the point where the insect has become entangled, 
and rl! upon it so as to cover it completely. When 
the captured insect is comparatively large the leaf itself folds 
over it. These movements bring a very large number of 
the digestive glands in contact with the insect, and the 
copious su Bly ot digestive fluid secreted promptly acts upon 
the anim y present, digesting certain constituents and 
rendering them fit for absorption by the plant. 
Dionaea, Venus’ fly-trap, is native to but one restricted 
locality near Witmington, North Carolina, in the vicinity 
of peat-bogs. The leaves, like those of many other carnivor- 
ous plants, are grouped in rosettes, and rest, for the most 
part, entirely or partially upon the ground. Each leaf con- 
sists (1) of a flat paddle-shaped petiole abruptly ending in 
