Plate B.— 5. Sweet Cherry tree on the left almost completely defoliated by 

 the Slug; tree on the right only slightly injured. 6. Galls on White 

 Spruce caused by Chermes similis. 7. Galls on Norway Spruce 

 caused by Chermes abietis. 

 (See pages 24 and 26.) 



[8] 



