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PROCEEDINGS OF THE ACADEMY OF 



[July, 



This specimen agrees fully in all diagnostic features with the type 

 and paratype before us. It is slightly smaller than the female 

 allotype and the coloration is less intense, the marginal fields of the 

 short almost circular tegmina being feebly darkened and only in 

 their proximal portion, the ventral surface of the caudal femora 

 showing very faintly an orange tinge and the caudal tibiae being a 

 much less intense glaucous. 



The broad prosternal spine, with cephalic face weakly concave and 

 distal margin broadly convex-truncate, is a striking feature in the 

 present insect. Though different in this respect and in male genitalic 

 features as well from M. reflexus, affinity to that species is clearly 

 indicated in the head, pronotum, form of tegmina and general type 

 of coloration. 



Melanoplus desultorius insignis new subspecies. 



This handsome insect is clearly the optimum development of the 

 species desultorius Rehn, showing sufficient differentiation to warrant 

 its recognition as a geographic race. From typical desultorius the 

 present insect differs in the larger size, richer greens of the body and 

 red of the antennae, more uniform coloration of the external faces of 

 the caudal femora and particularly in the more ample, conspicuously 



Fig. 4. — Melanoplus desultorius insignis new subspecies. 



Type. (X 3.) 



Lateral view of male. 



overlapping broad-ovate tegmina, which have their caudal margins 

 truncate and showing weak concavity at the apex of the humeral 

 trunk. 



Of the species of the Aridus Group, tristis Bruner shows the con- 

 dition developed under the most limiting environment, while desul- 

 torius represents a more favored development than aridus Scudder, 

 to which very close affinity is shoAvn. The male genitalia in all of 



