OF THE EARTHWORM. 129 
the presence of numerous small worms... . The 
phenomenon was so curious that I took up some 
of these worms and carried them into the house to 
examine them by the ight of my lamp. I imme- 
diately recognized them to be small Lumbrics, 
about fifteen millimétres long. Returning again 
into my garden, with a lantern, I saw at the same 
place many Lumbrics crawling upon the ground 
with their usual slow and regular mode of progres- 
sion. But they showed no lhght; and when the 
lantern was put out, their presence could not be 
recognized. But as soon as they were in their 
turn sprinkled with warm urine, the phosphores- 
cence of their entire bodies shone forth and illu- 
minated their wriggling movements.” 
The writer of this letter says he has since re- 
peated the experiment many times, and he asks 
if the phenomenon ought to be attributed to the 
saline matter contained in the urine, or if the 
warmth of this hquid is alone necessary to oc- 
casion the phosphorescence of Lumbrics. \ This 
might have been easily ascertained by using pure 
warm water in the experiment; but the author 
of the letter apparently did not think of it. His 
observation, as we have given it in his own words, 
tends to prove that violent muscular contraction 
excites an increase of phosphorescence in the 
earthworm as in the Noctiluca mentioned among 
animals in the preceding chapter; and the fact 
K 
