February 2, 1894. 
The Mystery of Worms in Rain. 
THE mysterious appearance of earth worms at certain 
times and places mentioned by Mr. Charles B. Palmer 
in Sctence, No. 570, is easily explained, it seems to me, by 
close observation of the worms under favorable conditions. 
Several of his queries are answered more or less directly by 
the following quotation from the manuscript of a little book 
on animal studies which I prepared saveral years ago, but 
which was never published: 
“¢ The time was in May during very rainy weather. The 
best place for observation wasa portion of the lawn over 
which earth had recently been spread several inches deep. 
The bare ground ofa garden which had not been disturbed 
since last year was almost as good. 
“On going out in the early evening, a constant slight 
snapping sound could be heard proceeding from the 
ground. Moving carefully, in order not to jar the ground 
and frighten the worms, a spot was selected for observa- 
tion. 
“* Looking closely, a dozen or more worms could be 
seen on each square foot of ground; some extended 
nearly full length on the surface, others protruding but 
aninch or so of the head. All were constantly moving 
the head about as if searching for something. Next 
morning several holes were found with blades of grass 
drawn partly in. 
“A two-gallon jar was nearly filled with moist earth 
and placed in the house, where a lampcould be used for 
observation at night. Some worms were put in and a 
few blades of grass placed on the earth. All the worms 
kept below the surface during the day, but in the evening 
were always active at the surface. 
““ One evening after a rain a worm was noticed crawl- 
ing on the second step of the porch. A few minutes 
later it was crawling along the wnder side of the projection 
of the third step and was soon over on the top investigat- 
ing things to its satisfaction.” 
Under ordinary conditions the worms remain concealed 
in their burrows during the day, but they habitually come 
to the surface at night, as is well known. ‘That they im- 
mediately seek to penetrate the earth on being dug 
up necessarily follows from their extreme wariness, which 
prompts them to retreat at the least sign of danger. When 
they come to the surface ‘‘to be pelted by the rain” I 
have no doubt that they are accepting the lesser of two 
evils by escaping a deluge underground. Having seena 
worm crawl comfortably along the under side of a painted 
board, I see no reason why it should not reach the roof 
and go down the conductor to the cistern. Nor does its 
climbing powers seem remarkable when we consider the 
moist, clinging body, and the peculiar organs of locomo- 
tion. 
This does not disprove the ‘‘rain down” theory, but 
only shows that, so far as earth worms are concerned, the 
phenomenon may have a more reasonable explanation. 
As to the sudden appearance of frogs after a shower, it is 
stated that this is a common occurrence in certain tropical 
countries, where the excessive heat and dryness drive 
them to seek shelter under leaves and earth till the cool- 
ing rain calls them out. In the month of August J have 
found live water beetles of the family Hydrophylide buried 
deeply in swamp earth, where they had retreated probably 
two months before when the last drop of water evaporated. 
The remarkable degree of adjustment to the evironment, 
which permits most animals of the lower orders to remain 
for a long time in a state of suspended activity, will doubt- 
less explain most of these mysterious apparitions when all 
the conditions are known. C. D. McLoutx. 
Muskegon, Mich,, Jan. 20, 1894. 
SCIENCE. | 67 
BOOK REVIEWS. 
An Elementary Treatise on Theoretical Mechanics. By 
ALEX. ZiwET. New York and London, Macmillan 
and Co. 1893, two vols.; 8vo, pp. 181,175. 
THE two volumes here mentioned contain, the one the 
outlines of kinematics, the other those of statics. A third 
volume, to include the treatment of dynamics, is promised 
later. The author, Professor Ziwet, of the University of 
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author and publisher. 
A System of Easy Lettering. By J. H. CRomMwetit. New 
York, Spon and Chamberlain, 1893, 27 p., r2mo, 
$0.50. 
Tuis little book is full of excellent illustrations of the 
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The selections are good, the work is excellent and the 
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Steam Machinery and the Marine Engine. By J. LAnG- 
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and New York, Macmillan & Co. 1893, 8vo, xv., 
267 p. New edition, revised and enlarged. 
TueEsE elementary lessons in steam marine machinery 
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are made to a stated scale, so that it is easy to ascertain 
