50 SOME INSECTS INJURIOUS TO TRUCK CROPS. 



ring in Colorado and Utah and has been found on sugar beets only 

 at Grand Junction, Colo. The adults of the species are almost in- 

 variably found on jDoplar trees, and it seems probable that the eggs 

 are deposited on twigs of the trees and that the nymphs drop to the 

 ground to find a home on the Chenopodium. The adults of Eutettix 

 strohi and E. seminuda are often found on trees and may have the 

 same habit. In the case of E. stroM and E. scitida, nearly all in- 

 stances of bad infestation have been near trees. In the case of E. 

 scitula these have been poplars, but two of the worst instances of 

 injury from E. strohi were alongside apple trees. 



Eutettix seminuda Say. — Eutettix seininuda is a white insect with 

 a brown saddle. It occurs from Kansas east to the Atlantic coast. 

 The nymphs are pale, with a brown saddle on the abdomen and some 

 brown on the thorax. Nothing is known as to their native food plant, 

 but from the close relationship to the preceding species it is likely 

 that it will prove to be a Chenopodium. There are two broods in a 

 season, the first one appearing slightly earlier than in the case of E. 

 strohi. Eutettix seminuda has been reported on beets in Illinois. It 

 does not occur in the West, where the writer has worked on beets. 



Eutettix clarimda Van Duzee (PI. I, fig. 4, a, &, <?, d). — Eutettix 

 clarivida is a green species with four black points on the margin of 

 the vertex. It occurs very commonly on the shad scale {Atriplex 

 confertifoUa) and on one or two other species of the same genus in 

 the arid regions. It has been found on beets at Grand Junction, Colo. 

 The nymphs are green, with two black spots on the vertex. The life 

 history is not known. 



Eutettix insana Ball (PI. I, fig. 7), E. alhida Ball, and E, pauper- 

 culata Ball occur on different species of Atriplex in the arid regions, 

 and may be expected to occur on the beets. 



Eutettix stricta Ball (PL I, fig. 8, «, h) is an Arizona species and 

 the nearest relative of E. tenella that we know. There is probably 

 more danger from this than from any other species of the group, 

 if the sugar beet should be introduced within its range. 



All the species of Agallia in a given section will be found attack- 

 ing the sugar beet more or less. Several of the species seem to be 

 almost omnivorous in food habits, but where they do show a pref- 

 erence it is for the relatives of the beet. For two of the species 

 {cinerea and higeloviw) a definite food plant is known, and in both 

 cases they are close relatives of the beet. The species of Agallia are 

 divided into two groups, based on structural and life-history charac- 

 ters. In one group, which includes sanguinolenta^ ulileri., cinerea., and 

 higelovim., they seem to prefer warm and rather dry situations, the 

 adults hibernating and spreading over the beet fields in the spring in 

 time to lay their eggs and produce their single brood of young there. 



66— IV 



