THE BLEACHED POTATO-STEM. 67 
wandering shoots of a pale yellow? And why did 
they wither away and die, leaving the empty 
flaccid outer membrane of the onion, as the only 
testimony to their ever having existed? It was 
not because there was no soil into which the 
fibrils of the roots might not have struck and 
found food. Neither was it for want of air, or 
warmth, or moisture. The following anecdote 
will prove that something beside all these was 
necessary. A potato lay in a dark place under- 
ground, where a few rays of light would occasion- 
ally steal in by a hole in the side. In due time it 
began to shew signs of life, and in a short while a 
tender sprout sprang from it. This sprout, like 
that of the blinded onions, wandered about striv- 
ing to escape from its dark den, until at length 
it got within the influence of the pencil of light- 
rays streaming in through the hole. Strange to 
say, it groped about no longer, but made directly 
for the hole, and before long actually pushed 
itself through, and appeared in the glad light of 
day above; here it grew, and became a healthy 
plant. On carefully looking at its stem, it was 
found, that all that portion of it which remained in 
the underground cavity, was almost white; but all 
