54 



Tachinid fly Cistogaster iinmaciilata 55 



Pennsylvania Bumblebee Bombiis pcnnsylvamcus 50, 52, 55, 176 



False Bumblebee Psithynts variabilis 176 



Eucerid bee Melissodes himaciilata 48 



Nomadid bee Bpcolus concolor 48, 52 



Halictid bee Halictus obscurus 55 



Halictid bee Halictus fasciatus 48, 52 



Black Digger-wasp Chlorion atratum 55 



Pennsylvania Digger-wasp Chlorion pennsylvanicum 55 



Myzinid wasp Myzine sexcincta 52, 55 



Ant Formica pallid e-fiiha schaufiissi 



iuccrta 52 



The general conditions of this prairie appear to have been less dis- 

 turbed than at Station I ; at least the prairie vegetation is more exten- 

 sive and uniform. The change in the vegetation is apparently greater 

 than the change in the kinds of animals. Their feeding and breeding 

 relations appear to be much like those at the prairie stations previously 

 discussed. 



In the flowers of the cup-leaved rosin-weed (Silphium integri- 

 foliinn) was found a giant bee-fly (Bxo prose pa fasciafa) which had 

 been captured by the ambush spider (Misiiuicna alcatoria), and on 

 webs in colonies of this same plant the garden spider (Argiope auran- 

 tia) was observed, with a grasshopper (Mclanoplus diffcrcntialis) en- 

 tangled in the web. From the flowers of this SilpJiiuui the following 

 insects were taken : Bpicauta margiuata and B. pcnnsylvanica, Rhyn- 

 chitcs ccneiis, Phymata fasciata, Bncoptoloplius sordidus, Melanoplus 

 diffcrentialis (nymph), Xiphidium strictum (adult and nymph), X. 

 attcnuatitni, Melissodes bitnaculata and obliqua, Bpcolus concolor, and 

 Halictus fasciatus. The margined blister-beetle (Bpicauta niarginata) 

 was found both upon the flowers and the leaves of the plant. On the 

 flowers of the purple prairie clover (Pctalosteniuui purpurcwni), Bom 

 bus pennsylvanicus, Xiphidium strictum, and BuscJiistus rariolarius 

 were taken. Collection 176 was taken from the flowers of Liatris 

 scariosa, and Nos. 55 and 178 from the flowers of Bryngium yiicci- 

 folinm. 



Swarms of the small corn syrphid, Mcsogramma politum, were 

 present, on one day settling by dozens on my hands and clothes, where 

 they were easily grasped by the wing. It had been a warm day, and 

 this swarming was in the sunshine at about 4 :30 p. m. The flies came 

 from a large corn field a few feet away. 



