Insects, etc., Injurious to the Plum. 



387 



but from personal observations it seems that when once a tree is 

 attacked it is doomed, unless some treatment is adopted. 



Unlike the Mussel Scale, which is found in the egg stage under 

 the " scale " during the winter, the Oyster-shell Bark Louse occurs 

 in the immature male and female condition. 



On lifting up one of the scales, say in February, one can easily 

 remove with a pin a small yellow body beneath the scale. This is 



[A. V. D. 



FIG. 258. THE OYSTER-SHELL BARK LOUSE 

 (A xpid iotus ostreteform is). 



the female insect not yet mature. Winged males appear in April 

 and early May, and fly around the scale-laden trees. The male is 

 yellow, with transparent wings and a dusky band running across 

 the thorax from the base of the wings. 



The females are then fertilised, and numerous eggs are laid, which 

 hatch into little active larva) in June, and they move over the tree. 

 These soon settle down, and the scale commences to form over them, 

 being quite prominent by October. 



2 c 2 



