20 REPORT ON INJURIOUS INSECTS FOR 1905. 



larvae, which had hatched out from eggs that had remained on 

 the trees during the winter. The trees were at once sprayed with 

 paraffin emulsion, which was repeated in seven days' time, and no 

 further specimens were seen. Previous, however, to spraying, some 

 of the larvae were removed and transferred to pot specimens under 

 glass, and the life-history noted. 



Growth was very rapid, and examples examined on May I2th 

 had developed into apterous viviparous females, and under the 

 microscope large numbers of the developing young could be seen 

 in their bodies. The colour is somewhat variable; most were a 

 deep green, but a few showed traces of brown. The antennae were 

 light brown, and the cornicles deep brown, and three faint-green 

 stripes on the abdomen. These gave rise to young, which again 

 developed into apterous viviparous females, and this continued 

 until nearly the end of May. On May 24th the rudiments of wings 

 appeared, and the pupal stage commenced. The pupae differ in 

 being of a shining green, with the wing cases edged with brown ; 

 the cornicles were almost wholly black ; in a few, slight traces of 

 green were present. By June 8th all were in the pupal condition. 

 From these, viviparous winged females appeared, and soon pro- 

 duced living young, which developed into apterous viviparous 

 females. These gave rise to further young, which rapidly assumed 

 the form of the parent, and these gave rise to other generations. 

 This continued until the end of September, when the pupal condi- 

 tion was again assumed, and from the pupae a generation of 

 winged males and wingless oviparous females appeared, the number 

 of females being in excess of the males. After fertilisation, the 

 females commenced to deposit their eggs on the stems, twigs, at the 

 base of the buds, etc., so that in the second week in October 

 numerous little shiny masses of bright blackish eggs were to be 

 found. 



The trees from which the progenitors of these specimens had 

 been removed were examined during the first week in October, and 

 on one or two a few wingless oviparous females were found (in 

 all probability they had come from escaped viviparous winged 

 females from the colonies under glass). The trees were sprayed 

 with paraffin emulsion, and carefully looked over in November, 

 but no eggs could be found. Many twigs were cut off and more 

 leisurely examined, but with the same result. It may, therefore, 

 be fairly concluded that the paraffin sprayfluid killed the 

 oviparous females before they had deposited their eggs. 



The life-history may be diagrammatically summarised as 

 follows : 



