TWENTY-SECOND REPORT OF STATE ENTOMOLOGIST 13 



work was conducted during 1927 and 1928. The average rain- 

 fall for May for a 25-year period is 2.09 inches. 



In May, 1927, the rainfall was excessive — 7.46 inches. 

 This produced abnormal flooded conditions during that season 

 and made control nearly impossible. On the other hand, during 

 May, 1928, there was only 0.26 inch, an excessively dry condi- 

 tion which, as before mentioned, made irrigation necessary on 

 a large scale and developed a July crop of mosquitoes in May. 

 During June, both in 1927 and 1928, conditions were very 

 nearly normal as indicated by June rainfall, but during both 

 years mosquitoes were unusually abundant, due to May con- 

 ditions. 1927 having excessive rainfall and 1928 having exces- 

 sive irrigation. During July the rainfall in 1927 was 3.67 

 inches and July, 1928, 5.17 as opposed to a normal of 1.73 

 inches. In 1927 the rainfall was more evenly distributed dur- 

 ing July, and control work was partially successful. However, 

 during July, 1928, the rains coming in almost a cloudburst and 

 producing flooded conditions made control work impossible. 

 However, during these two years much was learned about the 

 habits of mosquitoes and considerable data were compiled which 

 will help materially in control work in the future. 



Mr. G. A. Mail, who spent considerable time in Phillips 

 County doing experimental work during 1928, secured a consid- 

 erable amount of information regarding the life history and 

 habits of various species of mosquitoes, determining the time 

 necessary for mosquito eggs to hatch and discovering where 

 and how several species deposited their eggs as well as discover- 

 ing several new species that have not hitherto been recorded in 

 Montana. These mosquito studies should be continued for sev- 

 eral years, or until definite, practical recommendations for con- 

 trol can be made. In the Milk River Valley, mosquitoes are 

 a major pest from an agricultural standpoint and are of suffi- 

 cient importance to justify considerable time and money in 

 working out control measures. 



SUGAR-BEET LEAFHOPPER 



The sugar-beet leafhopper, Eutettix tenella Baker, often 

 called the white fly by the sugar-beet people, has been the sub- 

 ject of study for the past biennium. In cooperation with the 

 United States Bureau of Entomology, through their representa- 



