100 NATURAL RESOURCES SURVEY 



Brachys aerosa, Melsli. 



Eusattus convexus, Lee. 



Epeolus occidentalis, Cress. At Cretan texensis. 



* Exerna conspersa, Mann. On Fallugia. 



CRYSOTHAMNUS (BIGELOVIA) ASSOCIATION 



This association occupies the dissected edge of the mesa 

 and the higher gravelly parts of the valley of the Rio Grande. 

 It occupies these rapidly eroding and hence unstable situa- 

 tions and is as a consequence the most xeropytic of all of 

 our associations. Along the Rio Puerco we found this asso- 

 ciation immediately adjoining the Cedar Ass'n., while in the 

 Albuquerque region the broad mesa intervenes The reason 

 for this is that the Rio Puerco is higher allowing the Cedars 

 to creep down to the dissected edge of the valley. The plant 

 C. bigelovii after which this association is named stops ab- 

 ruptly and completely at the edge of the more level mesa. 

 It is very variable with many well-marked societies. 



Batyle saturalis, Say. On Thelesperma. 



Crossidius pulchellus, Lee. Exceedingly abundant on 

 Chrysothamnus when it blooms in late Sep. and Oct. 



Cysteodemus wislizeni, Lee. (S) Very common but apt 

 to occur in colonies which however are spread over much 

 ground. It occurs also on the mesa but not in the moun- 

 tains. About the base Mt. Taylor. 



Eusattus difficultic, Lee. 



E. reticulatus. 



* Epibragus canaliculatus, Say. Common also on the mesa 

 and in the Dalea Society. It eats the pollen of Rayless Gol- 

 den-rod and Gutierrezia. 



Holopepta Cacti, Lee 



Otidocephalus vittatus, Horn. On Chrysothamnus. 



HYMENOPTERA. 



Mellisodes menuacha, Cr. 



Osmia cerasi, Ckll. Chiefly at Phacelia corruga. Some on 

 chimaja. All in April. 



O. cyaneoniteus, Ckll. On same plants. 



O. hesperella. On Phacelia and cherry. One on a Pinon 

 cone. 



