310 
JOURNAL OF ECONOMIC ENTOMOLOGY 
[Vol. U 
does not occur on desert vegetation from Ryan to Keane Wonder and 
in the cultivated area at Furnace Creek ranch in the Death Valley. 
Imperial Valley 
In view of the fact that the same territory must be covered repeat¬ 
edly during a year, we have selected the Imperial Valley for more 
intensive work. Up to the present time the investigation has been 
carried on under desert and cultivated conditions and no attention has 
been given to the canyons, foothills and mountains. 
Ball suggests that the flights of the beet leafhopper may be “in the 
nature of migrations northward in the spring and southward in the 
fall. ,, If our interpretation of this statement is correct, we would 
expect to find the hoppers wintering over in the desert after their 
southward flight. Under desert conditions, however, only a few specie 
mens were captured on the foliage of the following plants: 
January 22, 1918, 3 E. tenella on gourd ( Cucurbita californica), 4 
miles west of Coyote Well near foothills. 
March 10, 1918, 2 E. tenella on creosote bush ( Larrea divaricata), 4 
miles west of Coyote Well near foothills. 
The beet leafhopper was extremely scarce at this time of the year on 
vegetation in desert areas within cultivated districts. Sweepings on 
desert vegetation in the vicinity of the Alamo River near Holtville, 
and the New River near Seeley and Brawley (Map 1 ), and also on vege¬ 
tation growing along the banks of these rivers, captured only an occa¬ 
sional specimen. 
An investigation was made at the boundary between the desert and 
cultivated area. A glance at the map shows that a main irrigation 
canal marks the boundary between the desert and cultivated land on 
the west side of the Imperial Valley. Between the San Diego and 
Arizona railroad tracks and the State Highway, desert collecting was 
started about one mile west of Dixieland and continued to the irriga¬ 
tion canal but not a single specimen was captured. Near the irriga¬ 
tion canal and in recently irrigated fields over one hundred adults and 
thirty nymphs were collected on the lowland or sea purslane ( Sesuvium 
sessile) on March 13-14. In the same vicinity a dozen hoppers were 
taken on Chinese pusley (Heliotropium curassavicum ). 
In January and March E. tenella was found in large numbers under 
cultivated conditions in all localities visited in the Imperial Valley on 
the Australian salt bush ( Atriplex semibaccata), a native plant of Aus¬ 
tralia. During a hot sunshine, sweepings on this plant near Calipa- 
1 The map is one issued by the Automobile Club of Southern California. It was 
not reproduced. Ed. 
