ADAPTATIONS TO ARID CONDITIONS IN CERCOPID2 
AND MEMBRACID-. 
By E. D. Bar. 
The frog-hoppers are distinguished from other Homoptera 
by the fact that the larvae envelope themselves in a mass of 
froth, using this no doubt as a means of protection from their 
enemies. Only a few species occur in the arid regions, but 
these are distributed through all but one of the genera occurring 
in the United States. 
The representatives of one of these genera, the Clastoptera, 
appear to have the same froth making habits in the arid region 
that they have in the humid. The larve usually occur early 
in the season, however, before the air has become very dry 
or are restricted in distribution to the higher mountains or to: 
exceptionally humid situations in the lower valleys. The 
other representatives of this group in the more arid regions 
apparently do not attempt to maintain froth masses exposed 
to the air, as none have ever been found. 
In a former paper* the writer showed the unique method 
employed by Aphrophora permutata Uhl. a western relative 
of the pine inhabiting species of the Appalachain region. ‘This. 
species was found on the roots and crowns of a Composite and 
a Legume, where they were protected from the sun and dry air. 
Since that writing the larve of A. annulata Ball has been 
found around the crown of Artemisia ludoviciana in Utah and 
the larve of Philaronia abjecta Uhl. on the roots and crowns. 
of Lupine and Geranium in the mountains of Colorado. The 
larvee of the other species of Philaronia (P. bilineata) occurring. 
in the mountains of Colorado has never been found, although 
the adults are among the commonest of the family. 
During several seasons collecting in California another 
species of Aphrophora, A. angulata Ball has been taken quite 
commonly in certain restricted areas along the coast. This 
species is closely related to the common A. binotata, common 
on grass and low vegetation east of the Rocky Mountains and 
whose spittle masses are often so abundant in the meadows 
as to be a nuisance. The California species was collected on 
*Ohio Naturalist, I, p. 122, 1901. 
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