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106 THE AMERICAN NATURALIST.  [VOL. XXXII. 
Variations of a similar nature were noted also in insects, and some 
of these are well known to entomologists who use cyanide bottles. 
Spiders and all of that group seem to be particularly resistant to the 
poison. The mites are the most resistant organisms thus far studied, 
but even among species of aphides some are much more sensitive 
than others. The red mite (Tetranychus telarius) is very resistant. 
In cases where complete paralysis is produced and there are no 
signs of life for several hours mites frequently recover. Some of the 
higher animals also behave in the same way. 
GILBERT H. Hicks: Effect of Light on the Germination of Seeds. 
Read by title. 
A. J. PIETERS: Efect of Alternating Dryness and Moisture on the 
Germination of Some Seeds. ‘The species experimented with were 
Chenopodium album, Daucus careta, Anthemis cotula, Arctium lappa, 
Cichorium intybus, Dianthus armeria, Echium vulgare, Datura tatula, 
Malva rotundifolia, and Verbascum blattaria. Two pots were devoted 
to each species. After the seeds were sown the pots were under 
uniform and like conditions, the soil being kept continuously moist. 
After a long period, during which germination had practically ceased, 
the soil in one of the two pots was allowed to become thoroughly dry, 
and remained so for two weeks. It was then moistened regularly, 
whereupon many seeds germinated. This was true of all the species 
mentioned. Two examples are selected at random from the list. 
Daucus carota: During the first 39 days pot A germinated 14%, and 
pot B 15%. No further germinations for 98 days. A was then kept 
dry for 14 days; Z moist as usual. Germination began in 4 2 days 
after watering, and in 4 days 4 germinated 15 %, while in the previous 
18 days B had germinated o. Both pots were subsequently left dry 
from August 7 to September 8, and then moistened. Germination in 
both pots began September 11, and in 17 days 4 germinated 9%; 
B, 30%. Dianthus armeria: In first 111 days A germinated 32%; 
B, 42%. A was then dried 14 days, while Æ was continued moist. 
Beginning July 27, 4 was moistened regularly. On July 30, germi- 
nation began in 4, and in 10 days A germinated 52%. During the 
previous 24 days Z germinated o. Both pots were dry from August 
7 to September 8, then both were regularly moistened. Germination 
began September 13. In 15 days 4 germinated 2%, and B 40%. 
Equally striking results were obtained with other species. In many 
cases germination began in the dried-out pots within 48 hours, and 
in some cases within 24 hours after the watering. A few other 
