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N.S. ENTOMOLOGICAL SOCIETY. 



NOTES ON THE YELLOW LEAF HOPPER OF THE BIRCH. 



> (Oncopsis sobrius Walk) 



By W. H. Brittain 



This species occurs quite commonly on birches in the vicinity of Truro and else- 

 where in Nova Scotia, and is also known to occur in other parts of the north easten- 

 United States and Canada. It is not nearly so abundant in this province as its rela- 

 tive, Oncopsis fitchi Van D., a species with an almost identical life history. 



The nymphs of this species were first noticed emerging from birch twigs in the la- 

 boratory by Mr. Gooderham in the spring of 1917. Examination revealed the presence 

 of eggs imbedded in many of the buds near the base and concealed by the bud scales. 

 The first nymph emerged in the laboratory on May 16th, but none was observed out- 

 of-doors until May 28th, the first adult reaied from the egg in our out door insectary 

 appeared on June 20th. 



The accompanying table gives details of the life histories of those insects that we 

 succeeded in rearing to maturity. Insects number 15 to 16 were kept in the laboratory 

 until after the third moult, when they were placed in the out-door ir sectary. Notwith- 

 standing tr e earliness of the season at which full development takes place there appears 

 to be but one brood a year. 



LIFE HISTORY OF YELLOW LEAF HOPPER OF THE BIRCH. 

 (Oncopsis sobrius Walk) 



