No. 466.] GENUS DI AD ASIA. 745 



Hab. Between Las Cruces and Mesilla Park, New Mexico, at flowers 

 of Sphceralcea fendleri lobata (Wooton), middle of August (Cockerell). It 

 was accompanied by Macroteropsis latior (Ckll.). 



The distribution of the species in States, etc., so far as known, 

 is as follows : 



MEXICO. D. diminuta Cr. ; sumichrasti Cr. ; enavata Cr. (Lower Cali- 

 fornia). 



CALIFORNIA. D. albovestita Prov. ; afflicta Cr. (tricincta Prov.) ; nigri- 

 frons Cr. ; bituberculata Cr. ; nitidifrons Ckll. ; laticauda Ckll. ; friesei 

 Ckll. ; enavata Cr. ; diminuta Cr. (Palm Spring, Davidson} ; australis 

 rinconis Ckll. ; australis opuntice Ckll. 



NEVADA. D. bituberculata Cr. 



ARIZONA. D. diminuta Cr. (Bill Williams' Fork, Snow, Grand 

 Canon, Hopkins) ; australis rinconis Ckll. (Bill Williams' Fork and Oak 

 Creek Canon, Snow) ; enavata Cr. (Oak Creek Canon, Snow). 



NEW MEXICO. D. diminuta Cr. ; sphceralcearum Ckll. ; australis Cr. ; 

 australis rinconis Ckll. ; enavata Cr. ; megamorpha Ckll. 



TEXAS. D. australis rinconis Ckll. (part of Cresson's original austra- 

 lis, as shown by a cotype) ; enavata Cr. ; enavata v. densa Cr. (a color 

 variation merely) ; afflicta Cr. 



KANSAS. D. australis Cr. (Wallace Co., and Morton Co., Snow); 

 enavata Cr. (Wallace Co., Snow) ; diminuta Cr. (Hamilton Co., Snow) ; 

 afflicta perafflicta Ckll. 



COLORADO. -D. enavata Cr. (Lamar, Snow, Palisade, Gillette, Jules- 

 burg, Ball, Trinidad, Titus) ; enavata v. densa Cr. (Rocky Ford, in beet 

 field, P. K. Blinn) ; diminuta Cr. (Fort Collins, Trinidad, Colo. Agric. 

 Coll) ; australis Cr. 



D. snmichrasti Cr., is peculiar for the densely punctured 

 mesothorax, but the blade of maxilla is broad at base and nar- 

 row apically, as in true Diadasia. The maxillary palpi are long, 

 6-jointed. The sexes do not look much alike, but close com- 

 parison confirms their identity. 



D. australis and its subspecies may be found visiting the 

 flowers of Opuntia. The small species, diminuta and its allies, 

 are addicted to the Malvaceae. D. megamorpha (?) was 

 recorded from the flowers of Sphceralcea angustifolia, but the 

 plant was really 6\ fendleri lobata, which had not then been 

 differentiated. 



UNIVERSITY OF COLORADO, 

 BOUI.DER, COLORADO. 



