﻿100 NINTH ANNUAL KEPORT 



and continued to hatch till the 10th of Januarj',lS77, when the remainder were exposed 

 again. The weather being subsequently mild, some hatched on each warm day until 

 the 26th. None hatched thereafter, and upon examination, subsequently, all were 

 found to have hatched. 



Experiment 3. — Fifty egg-masses exposed at same time. Brought in-doors Decem- 

 ber 1st. Kept there till the 22d without any of them hatching. Exposed again for 

 three weeks, and then brought in-doors on the 12th of Januarj\ They commenced 

 hatching two days thereafter, and continued till the 29th. Subsequent examination 

 showed them all to have hatched. 



Experiment 4- — One hundred egg-pods exposed at the same time, but alternately 

 brought in-doors and exposed again every 14 days. Some commenced hatching during 

 the second term in-doors ; others continued during the warm days of the third expo- 

 sure, and all had hatched by the sixth day of the third term in-doors. 



Expo'lment 5. — A lot of 100 egg-masses alternately exposed and brought in-doors 

 every week. During the tirst four terms of exposure they were continucfusly frozen, 

 while during the next four the weather was frequently mild enough to f)ermit hatch- 

 ing. They tirst began to hatch during the fourth term in-doors, and continued to 

 hatch, except during the colder days when exposed, until the seventh term in-doors, 

 during which tke last ones escaped. 



Experiment 6. — Many hundred egg-masses kept out-doors the whole time, first 

 commenced hatching March 2d. 



Experiment 7. — Many hundred pods, kept in-doors till December 15, and hatching 

 from November 28th up to that time, were then exposed, and have continned to hatch 

 whenever the weather permitted, and continue to hatch up to the present time 

 (March 10.) 



Experiment S. — A lot of 100 pods that had been hatching in-doors from November 

 19th, were exposed to fi-ost January 15th, and brought in-doors again January 2Sth, 

 where they continued hatching till February 10th. Every one was subsequently found 

 to have hatched. 



Experiment 9. — A lot of 100 under same conditions as in experiment 8, up to Janu- 

 ary 2Sth. They were then exposed again and brought in-doors February IGth, when 

 they commenced hatching and continued to do so till the 27th. All were found subse- 

 quently to have hatched. 



Two important conclusions are deducible from the above experi- 

 ment : 



First — Tlie eggs are far less susceptible to alternate freezing and 

 thawing than most of us, from analogy, have been inclined to believe. 

 Those who have paid attention to the subject, know full well that the 

 large proportion of insects that hibernate on or in the ground, are 

 more injuriously affected by a mild, alternately freezing and thawing 

 Winter, than by a steadily cold and severe one ; and the idea has quite 

 generally prevailed, that it was the same with regard to our locust 

 eggs. But, if so, then it is more owing to the mechanical action 

 which, by alternate expansion and contraction of the soil, heaves the 



