86 NATURAL RESOURCES SURVEY 



commonly show from a dozen to a hundred or more indivi- 

 duals. In addition to eating the pollen they frequently 

 consume the petals also. This insect was also taken from 

 among fungus mycelia under bark (in Spruce Assn.,) on 

 dead animals, under manure and stones, and on other 

 blossoms. 



Presmis pocularis, Dalm. One of the very noticable things 

 about this cactus is the abundance of dead and dying limbs 

 and whole plants. Although rabbits and starving cattle 

 help in producing this state of affairs, it is due chiefly to the 

 work of this and the next insect. This peculiar cerambycid 

 may be seen from June to Aug., on nearly all plants of this 

 species, which it apparently never leaves. The female is 

 usually to be seen carrying her much smaller mate, even 

 when engaged in ovipositing in the branches. The larvae 

 bore in the tissues of the plant causing extensive dark colored 

 areas and often the death of the branch. This long-horned 

 beetle, in its degenerate wings, dark color, and cylindrical 

 form, shows a most interesting resemblance to the Tene- 

 brionidae of the genus Eleodes so characteristic of this 

 region. As it never leaves its host it has no need of wings 

 which would probably be a disadvantuge in that it might be 

 blown off during the terrific sand storms of this region. 



Proarna valvata. This cicada is also very abundant on the 

 tree cactus, but, unlike the last, also occurs on the prickly 

 pears. During the last of June and the first half of July 

 the adults are abundant and the loud calls of the males are 

 heard on every hand when the sun is shining. But let a 

 cloud obscure the sky for a moment and all is hushed. They 

 suck the sap of the plant and here also the eggs are laid, an 

 operation that so engrosses the attention of the females that 

 they will frequently allow the collector to approach and pick 

 them off with the fingers. The larvae are to be found on the 

 roots of the cactus which thus furnishes them their food 

 throughout life. They lie in small mud cells among the roots 

 and apparently feed all winter as well as summer. 



Rhopalophorus longipes, Say. Was taken trom Croton 

 Texensis which is common in this society (N.) 



Tragidion coquus, L., also belongs here apparently as 

 does 



