10 



The Bulletin. 



On thickly-infested branches they often become so crowded that the 

 scales are piled over one another so that the real bark of the tree is 

 not visible at all. In such cases of very bad infestation the scales 

 often locate on the fruit, as shoAvn in Fig. 4. 



Fig. 4.— Infested twig natural size at right. Infested pear fruit natural size at left, showinfir 

 spots caused by scales. In center are shown a group of young scales and a single full-grown 

 female scale, all much enlarged. 



Slightly infested trees or branches will not be completely coated 

 over with the scales, and the bark may be of its ordinary color and 

 appearance except hero and there along the branches where the scat- 

 tering scales are fonnd. When the scales are scattering along the 

 branches each scale is often (but not always) in the center of a 

 slightly reddened spot on the bark. If the natural color of the bark 

 be reddish this will not show plainly, but if the bark is of a light 

 green or yellowish color the reddish spots are quite conspicuous. 

 Such reddish spots will be about the size as shown on the infested pear 

 fruit in Fig. 4. The gray scales themselves in the center of the spot 

 will vary from, the size of a ipin-head (in full-grown individuals) down 

 to the size of a pin-poin^ (in the very young). If the scale is dis- 

 covered while the trees are yet slightly infested there is no real reason 



