WILLIAMS: LARRID^ OF KANSAS. If 9 



Tachytes ohscurus Cress. 



This wasp was taken but once with her prey — a very small 

 acridian. 



Tachytes rufofasciatus Cress. 



This Tachytes, which has much the same appearance as 

 fuhnventris, was observed in Trego county, near those pictur- 

 esque chalk cliffs which skirt the sandy bed of the Smoky Hill 

 river. Here on July 13, 1912, several of these insects were 

 watched hunting their prey along the edge of a dense and 

 wide-spreading field of Russian thistle, dragging the victims a 

 short distance over these weeds and then over the adjoining 

 plowed ground to their burrows in the latter. The thistle sup- 

 ported an abundant population of largely immature Melanopli. 



Early in the morning a rufofasciatus was observed flying 

 from plant to plant and running hastily over the thistle tops in 

 quest of her prey. At 8 : 18 A. M. she caught and stung a locust 

 and dragged it laboriously over the disturbed soil to her nest. 

 At 8 :22 she secured another, with which it took her thirteen 

 minutes to reach her burrow. Upon reaching the same she let 

 go her prey, entered, and partly emerging head first, pulled 

 it in by the antennae. The wasp remained within forty min- 

 utes. This time was employed, perhaps, in closing a stored 

 cell or in excavating another. She was off hunting again at 

 9 :18 and five minutes later captured a small Melanopli nymph, 

 with which she flew to her abode. This was the only instance 

 in the locality where the smaller size of the victim permitted 

 of its being borne away in flight. Tachiftcs was off again to the 

 weeds, and at 9 : 55 pounced upon another Melanopli of a green 

 color. She clung strongly to the dorsum of the struggling in- 

 sect, and, stinging it under the thorax, soon quieted it. After 

 biting ( ?) it awhile under the thorax she straddled the insect 

 (which lay in an upright position), seized its antennae near 

 their base in her mandibles, and, holding the acridian as well 

 with her third pair of legs, began her journey. Here she made 

 use of her first two pafr of legs and augmented her progress 

 every now and then with a buzz of her wings. While in the 

 weeds the heavily laden insect strives to keep on top of the 

 Russian thistle, whence a leap (which she frequently essays in 

 an effort to make better headway) often brings her only a 

 little distance in advance and far down among the stems. 

 Nothing daunted, however, she struggles to the summit of 

 another plant, perhaps to repeat the performance. Several 



