502 ANNUAL REPORTS OF DEPARTMENT OF AGRICULTURE. 



IMPORTATIONS OF PARASITES OF THE ALFALFA WEEVIL. 



The difficulty of fighting the recently imported alfalfa weevil in 

 the alfalfa fields of Utah by mechanical and cultural means has 

 started an investigation as to its parasites in its original home. Mr. 

 Fiske, of the bureau, located at Naples, sent, in March and April, 

 large lots of the stems of alfalfa containing eggs of an allied weevil 

 parasitized by a minute parasite, all of which arrived in good condi- 

 tion in Salt Lake City, the parasites emerging in numbers^ and an 

 attempt is now being made by agents of the bureau to establish them 

 in the Utah fields. Three other species were sent later. 



IMPORTATIONS OF PARASITES OF THE IMPORTED ELM LEAF-BEETLE. 



The agent at Naples succeeded in sending over in good condition 

 eggs of the imported elm leaf-beetle, parasitized by a minute chal- 

 cidid — the same species imported three years ago, which has not been 

 rediscovered in the open in this country. He also sent over a dip- 

 terous parasite of the same insect, which also arrived in good con- 

 dition. Attempts are being made to establish both of these species. 



EXPORTATION S OF USEFUL INSECTS. 



An assistant in the bureau receiving a temporary appointment as 

 entomologist to the department of agriculture of Peru, especially 

 to study the injurious work of a scale insect on cotton, has been sent 

 during the year a number of shipments of a minute parasite of a 

 closely allied species from Washington. It is too early to announce 

 results. 



In the summer of 1910 Dr. L. P. de Bussy, biologist of the Tobacco 

 Planters' Association at Deli, Sumatra, visited the United States for 

 the purpose of investigating the damage to the tobacco crop by in- 

 sects and disease and to make an effort to import into Sumatra the 

 parasites of a destructive tobacco worm. Shipments of an egg para- 

 site of this insect have been started by agents of the bureau in Texas 

 and have gone to Sumatra via Amsterdam, but information as to 

 the results of these preliminary shipments has not yet reached this 

 country. 



The brown-tail moth having entered the Province of New Bruns- 

 wick, an agent of the Central Experimental Farm of the Dominion 

 of Canada has been sent there, and to him has been shipped a colony 

 of a dipterous parasite which has been established in Massachusetts 

 and which occurs there in very considerable abundance. 



It is considered most advisable to continue this attempt to assist 

 foreign Governments in this way wherever possible, since by this 

 course a most perfect understanding has been brought about among 

 the workers in these lines in the different countries, and the United 

 States has profited greatly by return courtesies of the same general 

 character. The official economic entomologists of all of the Govern- 

 ments of the world form practically a coherent body, with almost 

 identical interests and with every incentive for mutual assistance. 



WORK ON INSECTS AFFECTING SOUTHERN FIELD CROPS. 



The work on insects affecting southern field crops consisted of the 

 investigation of eight groups of problems, as follows: (1) The cot- 



