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UNIVERSITY OF CALIFORNIA EXPERIMENT STATION 



3. The olive psylla, Euphyllura olivina (Costa) (fig. 15). This 

 insect infests the young shoots, buds and flowers, causing the latter 

 to drop and prevents the setting of much of the young fruit. The 

 young psyllids are covered with a white cottony material which 

 entirely hides them from view. It occurs throughout southern 



Fig. 14. The olive thrips, PMoeothrips oleae (Costa). Adult female and work 

 of the insect on leaf and fruit of the olive. (Eedrawn from Del Guercio.) 



Fig. 15. The olive psylla, Euphyllura olivina (Costa), a, colony of young on 

 twig and flowers; &, nymph; c, adult. (Eedrawn from Coutance and Del 

 Guercio.) 



Europe and in Palestine and is a pest of minor importance except in 

 rare instances. 



4. The scale, Pollinia pollini (Costa). A soft scale attacking the 

 smaller branches of the olive trees in southern Europe. It was once 

 taken on a few olive trees at Pasadena, California, which were im- 

 ported from Italy in 1893. Alexander Craw at once promptly de- 



