142 The Rocky Mountain Locust. 



hatching. Exposed again for three weeks, and then brought in- 

 doors on the 12th of January. They commenced hatching two 

 days thereafter, and continued till the 29th. Subsequent exam- 

 ination 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 fourteen 

 days. Some commenced hatching during the second term in doors; 

 others continued during the warm days of the third exposure, and 

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



Experiment 5. — A lot of one hundred egg-masses alternately ex- 

 posed and brought in-doors every week. During the first four terms 

 of exposure they were continuously frozen, while during the next 

 four the weather was frequently mild enough to permit hatching. 

 They first began to hatch during the fourth term in-doors, and con- 

 tinued to hatch, except during the colder days when exposed, until 

 the seventh term in-doors, during which the last ones escaped. 



Experiment 6. — Many hundred egg-masses kept out-doors the 

 whole time, first commenced hatching March 2d, and continued 

 for thirty-eight days thereafter. 



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

 1 5th, and hatching from November 28th up to that time, were then 

 exposed, and continued to hatch whenever the weather permitted, 

 up to April 10th. < 



Experiment 8. — A lot of one hundred pods that had been hatching 

 in-doors from November 19th, were exposed to frost January 15th, 

 and brought in-doors again January 28th, where they continued 

 hatching till February 10th. Every one was subsequently fonnd 

 to have hatched. 



Experiment 9. — A lot of one hundred under same conditions as 

 in Experiment 8, up to January 28th. They were then exposed 

 again and brought in-doors February 16th, when they commenced 

 hatching and continued to do so till the 27th. All were found sub- 

 sequently to have hatched. 



Two important conclusions are deducible from the above 

 experiments : 



First — The eggs are far less susceptible to alternate freez- 

 ing and thawing than most of us, from analogy, have been 

 inclined to believe. Those who have paid attention to the 



