198 depaktmp:ntal reports. 



enemies of these plants in the countries named. The general report 

 on this trip will contain a description of the citrus enemies discovered 

 and studied, and will have a special importance in view of the greater 

 likelihood of the impoi'tation of citrus stock from the countries named 

 in future on account of our closer political I'elations with them. 



WORK ON INSECTS IN THEIR DIRECT RELATION TO THE HEALTH OF MAN. 



The question of insects as conveyers of disease to human beings, and 

 more particularly in the rural districts, has been the snb.ject of special 

 research for the past three years. A popular article by Dr. Howard 

 on this topic was published in the Yearbook for 1901, and, owing to 

 the great demand for information on this subject, this article was 

 republished as a Farmers' Bulletin. Since its issuance in the latter 

 form an average of between 20 and 30 letters per day have been 

 received requesting information on this subject and were answered 

 by the bulletin mentioned. This work covers more particularly the 

 insects concerned as carriers of malaria, in which certain mosquitoes 

 play the most important role, and typhoid fever, which is disseminated 

 by the house fly and related insects. The more important insect trans- 

 mitters of disease have been studied or are under investigation, but 

 we are in frequent receipt of material from this and other countries 

 which shows that there are still many insects which require study, 

 and this work will be prosecuted actively in the future. 



UNCLASSIFIED V^^ORK ON INJURIOUS INSECTS. 



During the last fiscal year investigations were taken up on supposed 

 insect damage to the cocoanut-palm industry in Cuba. More recently 

 we have had considerable correspondence with persons largely inter- 

 ested in the growing of these palms in Florida and in British Honduras. 

 As a result, an article has been prepared on the principal insects 

 which act as disseminators of the trouble whicli is locall}^ termed 

 "fever," and which appears to be due to a fungous disease. It 

 includes valuable suggestions based on reports received from prac- 

 tical growers as to the best methods for the prevention of the dissemi- 

 nation of the disease. 



In the fiscal year which ended June 30, 1901, a popular account of 

 the principal insect enemies of growing wheat was published, and 

 during the same year an extensive account of two very destructive 

 insects which affect cereal and forage as well as truck crops (the fall 

 armj' worm and the variegated cutworm) was completed and made 

 public. Certain minor insects which attack cereals have been taken 

 up in connection with other work, the list including the very injurious 

 corn root- worms, tlie lesser corn stalk-borer, and a species of corn 

 bill-bug new to science. An extensive account of the Southern grain 

 louse {Tojcopfera yraminurn) which was destructive in Texas to wheat 

 and some other cereals the same j^ear, was prepared and is now ready 

 for publication. A field agent of this oflice has been engaged to 

 investigate some of the insects w^hich injuriously affect the stems of 

 the suiall grains. Little of this work, however, has been done during 

 the present fiscal year, and the above brief mention of the facts is 

 sufficient for present purposes. 



Some investigations were conducted with a view to the ascertaining 

 of methods of control for certain insect enemies of mushrooms, and 

 a report on this subject is available for publication. 



