246 THE CANADIAN ENTOMOLOGIST. 



THE ELM LEAF BEETLE. 

 (Galeruca xanthomel.«na, Schrank.) 



BY JOHN B. SMITH, SC. D. 



My first practical acquaintance with this species began at New 

 Brunswick, N. J., in the spring of 18S9. In the Rutgers College campus 

 there are a considerable number of elms, many of them grand old trees, 

 which for several seasons in succession and up to 1888 had been defoli- 

 ated by Galeruca xanthomelcena, larva and imago. A double row of 

 young trees, many of them elms, extends from the College campus to the 

 Theological Seminary, a distance of about 280 yards, and at the beginning 

 of this row, most distant from the Seminary, the Experiment Station 

 building is situated. There are also a considerable number of elms 

 among the other shade trees in this part of the city. It was my intention 

 to protect the trees in and near the College campus, and near the Experi- 

 ment Station, from injury ; and, to obtain accurate data for a full history 

 of the species, I noted the dates of the principal occurrences in the life of 

 the insect. According to these notes, the hibernating beetles began 

 appearing in 1889 about the middle of April, very gradually increasing in 

 number to the beginning of May, when they became more plentiful. Eggs 

 were first noticed May 12, giving larvae May 24. The details of the 

 destructive measures adopted are immaterial here, and are published in 

 my Report for 1889. June 28 nearly all the beetles of the hibernating 

 brood had disappeared, and after July 3 no more were seen. At this time 

 all eggs were hatched. July 5th pupation was quite general, and imagos 

 of the summer brood were developing in numbers July 15. There was a 

 distinct period of a week or ten days during which no beetles could be 

 found, and at that time no unhatched eggs were on the trees. The watch 

 had been close, and I was positive that at the time the last of the hiber- 

 nating insects had disappeared, the larvc^ from the first lot of eggs laid 

 were no farther advanced than full fed and ready for pupation. After the 

 last days of June there were no egg masses to be found on the trees, and 

 by the middle of August the beetles had all disappeared. I felt positive 

 of my results, and published as a fact that the species was single brooded 

 at New Brunswick. This was contrary to all that had been previously 

 written ; but in no published accounts were details of actual observations 

 given. I repeated my observations in 1890 and 1891, and presented 

 them at the Washington meeting of the Club. Dr. Riley felt quite certain 

 that I was mistaken, though he could not question my observations, while 



