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producing for 6 or 7 weeks. The newly born scales are micro- 

 scopic in size and remain under the parent scale for a short 

 time, finally coming out to wander about for a while until they 

 find a suitable place on the bark to locate. As soon as they 

 settle down, the waxy thread like secretions begin to appear on 

 their backs. These secretions foi-'m the scales. Owing to the 

 compartively long period during which young are produced it is 

 difficult to ascertain hov; many generations occur in a year. 

 Judging from the scales as they appear in winter, however, it is 

 probable that the youiig are produced xintil the latter part of the 

 summer or early in the fall. After all their young have been 

 produced, the old females die, the young surviving to continue 

 the species. 



The Oyster Shell scale or Oyster-shell Bark Louse as it is 

 usually called is very similar in life history to the San Jose 

 scale. The main difference are that whereas the Saji Jose young 

 are born alive, the oyster shell yoixng are hatched from eggs, and 

 again, whereas the San Jose female gives birth to 400 or more, 

 the oyster shell female gives birth to but froiv. 40 to 60, 

 The latter is not so destructive or so rapidly disseminated as 

 the San Jose but in many districts- noticeably in the neighborhood 

 of Elmira, N, Y.- it causes much damage. It is expecially pre- 

 valent in localities where its developement has never ^oeen 

 checked, i.e., where the trees have been allov/ed to deteriorate 

 and go to ruin. It would be well to look for this insect, 

 therefore, along with San Jose Scale where the work of renovation 

 is comtemplated. 



For both these pests it has been recommended to spray with 

 lime sulphur ?/ash, using the commercial article at a concentra- 



