41 



which in February or March could be taken out and burned. Where 

 the buildings could be kept closed during the early summer the hatch- 

 ing moths would eventually die, thus avoiding the necessity of fumiga- 

 ting. These remedies will doubtless be of value where apples are 

 treated as indicated, the last two being mere variations of older sug- 

 gestions. 



THE ENTOMOLOGICAL SOCIETY OF WASHINGTON. 



June 5, 1890. —Mr. Ashmead, under general notes, announced the discovery of a 

 genus of Proctotrupidae new to the United States. The insect Iphitrachelus ameri- 

 canus is interesting as furnishing a counecting form between the subfamilies Cera- 

 phrouinie and Platygasterinai. 



Mr. Schwarz exhibited a specimen of Throscus piignax, which species is new to the 

 fauna of the District. 



Professor Riley presented a paper " On the Difficulty of Dealing with Lachnos- 

 terna," in which he described the attacks of these beetles on certain large trees, espe- 

 cially a Chestnut and a Swamp Oak having a height of about 30 feet, which had 

 been transplanted to his grounds last February. The successive appearance and 

 work of several species of Lachnosterna were described and the experiments with 

 remedies detailed. The latter consisted in spraying with a strong whale-oil and to- 

 bacco-soap solution, and later with London Purple at the rate of 1 pound to 125 gal- 

 lons of water. 



The applications were satisfactorily made, but proved ineffective. The first did 

 not prevent the attacks of the beetles at all, and while the second resulted in the 

 l)ui8oning of many of the beetles, as indicated by the finding of dead ones on the 

 ground, it was of little value in limiting the onslaught. Professor Riley deduced 

 from his experiments that it was practically impossible to protect large trees from 

 Lachnosterna. It was shown also that the beetles came from the ground near the 

 trees. The injury consisted in the gnawing off of the leaves at the base of the 

 petiole. 



The paper was discussed by Messrs. Fernow, Riley, Schwarz, Howard and Mann. 

 In a paper entitled "Notes on Xylehorus" Mr. Schwarz commented upon the dis- 

 covery of a wild food-plant of Xyleborus dispay- (pyri). This Scolytid had been found 

 quite recently in the vicinity boring and ovipositing in young shoots of Liriodendron 

 tulipifera. In the same branches another species, X. tachygrapJiua, was discovered, 

 and Mr. Schwarz exhibited and described its galleries. 



Discussion followed by Messrs. Riley, Schwarz, Ashmead, and Fernow. 



Mr. Howard read a paper entitled " The habits of Eurytorna," in which he called 

 attention to the fact that heretofore the generally-surmised parasitic habit of the 

 members of this genus had never been conclusively shown ; and the close relation- 

 ship of Eurytoma with the phytophagic genus Isosoma would lead to the inference 

 that the former might be, in part at least, inquilines and not true parasites. 



The following of a certain species from the larval stage to the pupal, in which they 

 were at once recognized as a species of Eurytoma* settled in one instance at least the 

 question of larval habit. An Oak gall, Cynips quercus-jn-uniis, was found, on cutting 

 it open May 17, to contain six full-grown parasitic larvae, afterwards determined as 

 given above, and the remains of a larva which they had nearly devoured. 



The paper was discussed by Messrs. Riley, Howard, and Ashmead. 



C. L. Marlatt, 



Recording Secretary. 



* The imagos obtained later proved to be Eurytoma prunicola Walsh. 



