THE EVENING PRIMROSE 
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of night, with its uneartiily sound, flits ever and anon 
from the ivy, across the green. 
“Night’s voices are awaking: from the lone 
Elf-haunted cavern, hark their stilly calls. 
The winds are lulled by their sweet whisperings, 
The wearied flowers, earth’s rainbows, lay them down. 
With folded leaves in clusters.” 
Naturally as we shrink from darkness — even by in- 
stinct, before w'e have heard those fearful tales which 
make it terrific to childhood — still we can but contem'- 
plate the veil of night wfith gratitude to the Beneficent 
Creator. Little need be said of the value of sleep to 
mankind; the daily awakening in strength, of the mind 
and body, which languidly sank to rest an the preceding 
evening, occurs to all, and is favoured by darkness. 
But the sleep of the vegetable differs in one respect 
from that of the animal, that it is not caused by its ex- 
hausted powers; but when light, which acts as a sti- 
mulus, is withdrawn, then the stalks of compound leaves 
hang back, and fold their leaflets together, or the leaves 
droop over the flowers, or cover the fruits, so as to shel- 
ter them from the cold dews. This was termed by Lin- 
naeus, the sleep of plants, and said by him to be analo- 
gous to the action of spreading the wing, by which some 
birds shelter their young during night. It is generally 
thought that Linnaeus’s term is somewhat hyberbolical ; 
but that the cessation of the stimmlus of light, and the 
constrained position of the flower and foliage, may be 
advantageous to the vegetable constitution, in a way 
somewhat similar to that in which it is beneficial to the 
animal system. Sir James Smith remarks, that as the 
infant requires a fuller measure of sleep than is needed 
by the man, so the young plant is more thoroughly closed 
during night than the older one. 
All blossoms, if we except the few which, like the 
evening primrose, are open during night, are more or 
less affected by what is termed the sleep of plants ; and 
the leaves of leguminous plants, as the pea, the lupin, 
and the clover, experience it very sensibly. Pinnated 
leaves are more sensitive than any others. These are 
