Horn.] lUU [Feb. 21, 



0. magister. Horn. Trans. Am. Ent. Soc. 1870, p. 90. 



Head and thorax orange yellow, shining, very sparsely punctulate. 

 Antennae brown, basal joint yellow. Thorax sub-pentagonal, sides 

 moderately prominent, disc flattened. Elytra piceous, surface with very 

 coarse reticulations. Body beneath piceous, middle of pectus frequently 

 yellow. Legs and coxae, orange yellow, glabrous, tarsi brownish. Length 

 .90-1.40 inch ; 23-35 mm. 



Male. Antenna? as in melaena. Fifth ventral truncate, sixth deeply 

 emarginate, lateral processes moderately prominent. Last dorsal seg- 

 ment oval at tip. Middle tibiae feebly arcuate not flattened. 



Female. Antennae as is melaena. Fifth ventral sub-truncate, sixth 

 moderately prominent and sub-truncate at tip. 



Hind tibial spurs similar to each other, slender. The largest species 

 of the genus in our fauna. Occurs from Owen's Valley, California, to 

 the Gila River, Arizona. 



0. vulnerata, Lee. Ann. Lye. V, p. 159 ; Proc. Acad. 1853, p. 331 ; var. 

 Cooperi, Lee. Proc. Acad. 1854, p. 18 ; Pacif. R. R. Rep. 1857, p. 51, pi. 

 2, fig. 6. 



Head orange yellow, between the eyes piceous, surface nearly impunc- 

 tured. Thorax pentagonal, lateral angles prominent, disc flattened, 

 smooth, color orange yellow, frequently with broad median piceous 

 stripe. Elytra black sculpture variable. Body beneath and legs black, 

 moderately shining. Length .40-1.10 inch ; 10-28 mm. 



Var. vulnerata, Lee. Elytra scabrous varying to finely reticulate. 



Var. Cooperi, Lee. Elytra coarsely reticulate varying to finely reticu- 

 late. 



Male, as in melaena. Fifth ventral sub-emarginate, sixth deeply 

 emarginate with lateral processes moderately protuberant. Last dorsal 

 segment acutely oval at tip. 



Female. Fifth ventral sub-emarginate, sixth oval and sub-truncate at 

 tip. Last dorsal oval at tip. 



Outer spur of hind tibi;e stouter than the inner and slightly dilated 

 at tip. 



Occurs from Fort Tejon southward to San Diego, thence north to 

 Owen's Valley, California, and thence by the desert regions of Nevada 

 to Southern Oregon. Very abundant. 



C.Nuttali, Say, Journ. Acad. Ill, p. 300; Am. Ent. pi. 3; Proc. Acad. 

 1853, p. 334 ; falgifer, Lee. Jour. Ac. N. S. I, p. 90 ; Proc. Ac. loc. cit. 



Head brilliantly aeneous, sparsely punctate. Thorax sub-pentagonal 

 surface of disc irregular, shining, sparsely punctate, and brilliantly 

 aeneous, sometimes with bluish or cupreous tinge. Elytra with brilliant 

 cupreo-metallic lustre, surface finely reticulato-scabrous. Body beneath 

 and legs metallic green. Length .64-1.10 inch ; 16-28 mm. 



Male. Antennae as in melaena. Fifth ventral broadly emarginate, emar- 

 gination at bottom bisinuate, lateral lobes obtuse, moderately prominent, 

 sixth ventral produced, deeply cleft and pilose at apex. Last dorsal 



