284 JOURNAL OF ECONOMIC ENTOMOLOGY [Vol. 1 



"My observations have not beeu suflaeiently complete so that I can state that 

 the egg-layinj; puncture is made in a different way from that just described, 

 and that, for example, the numerous thrusts of the piercing organ may not be 

 intended to disarrange the contents and to arrest the embryonic developmeut.1 



"If I can get sufficient material, it appears to me that it would be quite 

 possible this year, by commencing to make these observations at an earlier 

 date, to learn more accurately the history of the curious phenomena which 

 accompany the egg laying of this species. I shall hope to find out also how 

 the other generations go on and in what condition and in what stage the 

 Tetrastichus passes the winter, and whether it can attack other eggs than 

 those of the elm leaf-beetle." 



Visiting Doctor Marchal in June, 1905, after the publication of this 

 interesting article, the writer asked him whether he had beeu able to 

 make his further observations, and he replied that the elm leaf-beetle 

 had so entirely disappeared in the vicinity of Paris that he had not 

 been al)le to do so. The writer urged him to make an effort through 

 his correspondents to secure parasitized eggs of the Galerucella for 

 sending to the United States in an effort to introduce and establish 

 this important parasite on this side of the Atlantic. It was consid- 

 ered practically hopeless to attempt the introduction that summer, as 

 the time was so late and it was not then known just in what part of 

 France the elm leaf-beetle could be found abundantly. , During 1906 

 practically the same conditions existed; a locality was found. l)ut the 

 parasites did not seem to be present. In 1907, reaching Paris about 

 the first of May, the writer again reminded Doctor ]\Iarehal of his 

 desire to import the parasite into the United States, and. meeting Mr. 

 Charles Debreuil, of Melun, at the residence of the Baron de Guerne, 

 the subject was brought up again, and M. Debreuil later in the season 

 forwarded eggs of Galerucella to the United States, which were 

 promptly sent to the parasite laboratory at North Saugus, Mass. ; but 

 the time was too late and the parasites had emerged and died. • 



In April, 1908, the Entomological Society of France was good 

 enough to publish in its Bulletin (No. 7), page 86. a request from 

 the writer that eggs of the elm Galerucella should be sent to the 

 United States for the purpose of rearing parasites. This notice 

 brought a speedy and effective response. About the 20th of ^lay. Pro- 

 fessor Valery Mayet, of MontpeUier, France, a personal friend of the 

 writer, secured a number of leaves of the European elm earning egg- 

 masses of the Galerucella. placed them in a tight tjn box and mailed 

 them to the writer's office in Washington. They were received on 



'"This hypothesis appears to me somewhat pi-ohahle. The arrest of tlie emhryonie de- 

 velopment of the host seems really a condition useful for the evolution of tlie ejig of 

 the parasite, and one of the functions of the multiple thrusts of the oviijositor is 

 rather probably to stop it." 



