June, ’18] 
309 
SEVERIN AND THOMAS: BEET LEAFHOPPER 
Although the senior writer was engaged in a study of the anatomy 
and histology of the internal organs of E. tenella as a foundation for 
the life cycle of the causal organism of curly-leaf of sugar beets if such 
occurs in the insect, we considered it our patriotic duty to temporarily 
abandon this phase of the problem, and spend a considerable amount 
of time in the field during the period of the war. Since Ball believes 
that the beet leafhopper breeds in arid or desert regions, and that the 
migration of enormous numbers of this pest have caused three serious 
and widespread outbreaks of curly-leaf in California and one in Utah 
in 1915, from flights of the California outbreaks in 1914, an investiga¬ 
tion was started to determine where this insect spends the winter and 
to locate the breeding areas in this state. He states, “Any informa¬ 
tion by which the probable occurrence of these periodic outbreaks 
could be foretold would, therefore, be worth millions of dollars to this 
industry.” 
Trips have been taken into the San Joaquin Valley, to the Tulare 
Lake and Bakersfield district, Salinas Valley, Mojave Desert, Death 
Valley, Imperial Valley and to sugar beet fields in various parts of the 
state. After a general survey of the enormous territory, it soon became 
evident that it would require several years of field work before definite 
conclusions could be drawn in regard to the breeding areas of this 
insect. We shall, therefore, confine our attention to the results so far 
obtained in the Death Valley and Imperial Valley. 
Death Valley 
On January 27-31, a trip was taken into the Death Valley and 
sweepings were made on desert vegetation from Ryan to Keane Won¬ 
der, a distance of thirty-eight miles, and on cultivated vegetation at 
Furnace Creek ranch situated about midway between the two towns. 
No E. .tenella were captured on desert vegetation; such as cattle spin¬ 
ach (Atriplex polycarpa), desert holly (A. hymenelytra) , alkali blite 
(Suaeda moquini), creosote bush ( Larrea divaricata), mesquite (Pro- 
sopis juliflora) and other undetermined plants. No beet leaf hoppers 
were caught on salt grass ( Disticlilis spicata ), Kern greasewood (Spi- 
rostachys occidentalis) and salt rush ( Juncus leseurii) growing near the 
margin of the salt marshes. No specimens were taken on mesquite, 
arrow-wood (Pluchea sericea ) and Bermuda grass (Cynodon dactylon) 
growing along Furnace Creek. No hoppers were captured under cul¬ 
tivated conditions at Furnace Creek ranch on alfalfa, cheese weed 
(Malva parviflora), nettle-leaf goosefoot ( Chenopodium mnrale), Ber¬ 
muda grass, and on arrow-wood and Bermuda grass growing along the 
irrigation ditches. If we are justified in drawing conclusions from the 
investigations carried on at this time of the year, apparently E . tenella 
