158 



Insect Pests. 



As much as seven days' difference was noticed at one place by 

 Mr. Furley (at 1'invin) ; those on the Blenheim Orange hatched on 

 the 3rd of April, those on the Wellington not until the 10th of April, 

 and it was particularly noticed that they hatched first on the Eck- 

 Hnville, one of the earliest of apples. Not many miles away at 

 Eardiston they did not commence to appear until the 12th. 



In Kent they have been found to vary in incubation between 

 the 24th of March and the 27th of April. 



Schmidberger records them as hatching in Germany on the 5th of 



April, simultaneously with the 

 bursting of the leaves. 



The small larvae coming from 

 the ova at once ascend to the 

 buds, and if they are not suffi- 

 ciently open they may be seen 

 seated on the buds waiting to 

 gain entrance (Fig. 133). 



At first the larvae are yellow 

 to dirty yellow with brown 

 markings, bright red eyes, brown 

 feet, and about the size of a pin- 

 point ; their form is seen in the 

 photograph (Fig. 129). They are 

 quite flat, and soon work their 

 way into the folds of the buds 

 and at once commence to feed. 

 Sometimes these little larvae are 

 quite green, at others quite dark 

 in colour. 



Schmidberger found that the 

 larvae cast their skin on the 

 second day after birth, and soon 

 after this that characteristic 

 globule, seen on the buds and open trusses, makes its appearance from 

 the larval body, and then the white thread appears by which the oily 

 globule is attached. Another moult takes place in a few days, and then 

 the larva not only is provided with the thread and globule but also with 

 a number of white waxy threads which partly cover its body. The 

 first change I have found may take place ten days after hatching. 

 Until recently the first moult observed by Schmidberger was not seen. 

 In no case have I been able to detect moulting as soon as Schmid- 

 berger describes. After changing the second skin the Psylla becomes 



[A. \ r . D. liintoul. 



FIG. 132. OVA OF APPLE SUCKER, 

 SHOWING WHERE DEPOSITED. 



(Slightly magnified.) 



