42 



Though it was an almost pure stand of slough grass, with this were 

 mixed a few plants of wild rye (Ulymus vkgitdcus submuticus and B. 

 canadensis). These grasses reach a height of about four feet. The 

 ground was very hard and dry, and there were large cracks in it, 

 A single collection of animals was made here, No. 179. 



Common Names Scientific Names 



Common Garden Spider Argiope aurantia 



Ambush Spider Misumena aleatoria 

 Differential Grasshopper, adult 



and nymphs Melanoplus differentialis 

 Red-legged Grasshopper, adult 



and nymphs Melanoplus femur-ruhrum 



Texan Katydid Scudderia texensis 



Meadow Grasshopper Orchelimum vulgare, adult, and 



nymphs of vulgare or glaberri- 

 mum. 



Dorsal-striped Grasshopper Xiphidium strictum 



Black-horned Meadow Cricket CBcanthus nigricornis 



Four-spotted White Cricket CBcanthus quadripunctatus 



Ground-beetle Leptotrachelus dorsalis 



Sciomyzid fly Tetanocera plumosa 



The basic food-supply in such a habitat is of course the grasses, and 

 this fact fully accounts for the presence of large numbers of individ- 

 uals which feed upon grasses, as do the Orthoptera in general. But 

 the Orthoptera listed are not exclusively vegetable feeders, for Forbes 

 ('05 : 147) has shown that Xiphidium strictum feeds mainly upon in- 

 sects, chiefly plant-lice, as well as upon vegetable tissues, including fun- 

 gi and pollen; Orchelimum vulgare (p. 144), largely upon plant-lice 

 and other insects ; and CBcanthus quadripunctatus (p. 220), upon plant 

 tissues, pollen, fungi, and plant-lice. These observations were based 

 upon a study of the contents of the digestive tract. The food of the 

 sciomyzid fly is unknown. The garden spider lives exclusively upon ani- 

 mal food; and being abundant, it must exert considerable influence 

 upon other small animals. It not only destroys animals for its food, but 

 many others are ensnared in its web and thus killed. In one of the 

 webs I found a large dififerential grasshopper. The rank growth of 

 vegetation furnishes the necessary support for the webs of this spider. 



Some of the insects, as Melanoplus differentialis and M. femur- 

 rubrum, oviposit in the soil, but others — Scudderia texensis, Xiphid- 

 ium strictum, Orchelimum vulgare, and CBcanthus — deposit their 



