and beneath, black ; bands of the abdomen unin- 

 terrupted ; lateral spot of the first band obsolete 

 or wanting ; anal spines none. Length to the tip 

 of the wings, one inch and a fifth. 



Female. Ferruginous; basal band of the ab- 

 domen, and sometimes the second and third 

 bands, interrupted in the middle ; lateral spot of 

 the first abdominal band very oblique. Length 

 to the tip of the wings, one inch and three- 

 fifths. 



OBSERVATIONS. 



This remarkably fine and new species is very 

 distinct from the speciosus of Drury, and is some- 

 what larger than that common insect. When 

 descending along the bank of the Arkansa river, 

 with a detachment of Major Long's exploring 

 party, I had frequent opportunities of observing 

 this species. It generally occurred upon flowers, 

 in company with many other interesting Hymen- 

 opterous insects. It is highly probable, that, 

 like the speciosus, the grandis nidificates in the 

 earth, and feeds its larvae with the dead bodies of 

 Cicada. 



The speciosus. grandis, and a few other large 

 species, ought to constitute a distinct division in 



PLATE II. 



