86 



THE BEPOET OF THE 



No. 36 



Further data on the duration of the nymphal stage of summer and winter 

 forms are presented in Tables No. 3 and 4. 



TABLE No. 8. 



Year 



Length of Nymphal Life of Summer Forms. 



Date of 

 Hatching. 



Generation. 



Number of 

 Individuals. 



Duration. 



Max. i Min. 



Aver. 



1917.... 

 1917.... 

 1918.... 

 Average 

 1917.... 

 1918.... 

 Average 

 1917.... 



May 11-31. 

 June 5-30 . 

 June 18-24. 

 June 5-30. 

 July 3-30. 

 July 26-29. 

 July 3-30. 

 Aug. 4-5.. 



1st 

 1st, 2nd 



2nd 

 1st, 2nd 



2nd 



3rd 

 2nd, 3rd 



2nd 



71 



40 

 10 

 50 



143 

 8 



151 

 11 



days 

 SO 



21 



25i 



23 



17 



224 



20 



23 



TABLE No. 4. 



Year. 



Length of Nymphal Life cf Overwinteihig Forms. 



Date of 

 Hatching. 



Generation. 



Number of 

 Individuals. 



Duration. 



Max. 



Min. 



Aver. 



1917.... 

 1917 . . . . 

 1918.... 

 Average 

 1917.... 



Aug. 19.... 

 Aug. 1-30. 

 Aug. 26-31. 

 Aug. 1-31. 

 Sept. 1-8.. 



2nd 

 3rd 

 4 th 

 3rd, 4th 

 3rd 



6 

 22 

 11 



33 

 5 



days 

 23J 



38 



43 



401 



58 



The Summer Adult. 



The summer adult commences to appear a short time after the pear blossoms 

 fall, and from then until early autumn it is always present. 



Description: The adult (Fig. IS) is a tiny four-winged insect bearing a 

 striking resemblance to a Cicada in miniature. The transparent wings slope roof- 

 like over the abdomen, and the legs are adapted for jumping. The differences 

 in the external appearance of the male and female are shown in Fig. 21. The 

 female is about 2 mm. in length and the male about 1.8 mm. 



