28 DESCRIPTION OF PLATES. 



PLATE IV. 



Paper birch aphid. 

 FIG. 93. First spermatocyte, metaphase. 



Clover aphid. 



94. First spermatocyte, metaphase. 

 95-96. First spermatocyte, prophase. 



Woolly beech aphid. 



97-98. First spermatocyte, metaphase. 



99. Second spermatocyte, metaphase. 

 TOO-IOI. First spermatocyte, anaphase. 



Star cucumber aphid. 



102-103. First spermatocyte, growth stage. 



104. First spermatocyte, prophase. 



105. First spermatocyte, metaphase, Hermann preparation. 



106. First spermatocyte, metaphase, Gilson. 



107. First spermatocyte, early anaphase. 



108 a and b. Second spermatocyte, anaphase. 

 109. Second spermatocyte, anaphase. 



Maple aphid. 



no. First spermatocyte, metaphase. 

 1 1 1- 1 12. First spermatocyte, anaphase. 



113. First spermatocyte, prophase. 



Pea aphid. 



114. Parthenogenetic egg, metaphase of maturation spindle. 



115-116. Parthenogenetic egg, 32-cell stage, metaphase of segmentation spindle. 



Goumi aphid. 



117-118. Winter egg, polar bodies. 



119. Winter egg, male and female pronuclei. 



1 20 a and b. Winter egg, prophase of segmentation mitosis. 



