THE PEAK III KIPS UN CAI IKOKXIA. 



29 



Average mean temperature For month of February, 1910 19. 



.Mean maximum temperature for month of March, L910 GG. 2 



Mean minimum temperature for month of March., 1910 44. 5 



Average mean temperature for month of March, 1910 55. 



Mean maximum temperature for month of February, I ill I 56. 5 



Mean minimum temperature for month of February, 191 1 37. 3 



Average mean temperal lire for month of February, 1911 46. 9 



Mean maximum temperature for month of March, 1911 63. 3 



Mean minimum temperature for month of March, 1911 46. 



Average mean temperature for month of March, 1911 54. 6 



2200 

 2/0O 

 2000 

 /900 



teoo 



/700 



/eoo 

 /soo 



/400 

 /300 

 /200 



//oo 

 /ooo 



300 

 6VO 

 700 

 600 

 SOO 

 400 

 300 

 200 

 /OO 

 O 



Fig. 10. — Curve showing emergence of adult pear thrips in cages under trees in field, at Walnut Creek, 



Cal., 1910. (Original.) 



It will be seen from the temperature records (Table II) that while 

 February, 1909, had 2 degrees higher average mean temperature 

 than February of 1910, March of 1909 had 5 degrees less average 

 mean temperature than March of 1910, making the average mean 

 temperature for the months in which most of the adults emerged 

 50.5° F. in the year 1909 and 52° F. in the year 1910. Another factor 

 which held back the emergence greatly the former year was the 



































































































































































































































































































































































































































































































































































































































































































































































































































































































































































































































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