LOCUSTS. 51 



wings striped lengthwise above with various shades of yellowish 

 brown, and deeper brown, or with deep brown striped with a still 

 deeper shade ; the hind shaul^s coral-red, with white spines, black at 

 the tips. The narrow parchment-like upper wings with a pale narrow 

 stripe at the fore edge, and also for rather more than half the length 

 at the hinder edge, with an area between the two stripes, narrow at 

 the base and gradually widening, marked with angular brown blotches, 

 these dark near the base, and fainter towards the tip of the wing. 

 Beneath these elytra or upper wings is folded a pair of delicately 

 transparent wings of ample size. 



The colours of the body were necessarily to some degree altered 

 by the conditions of transit, but the accompanying figure of the 

 "American Acridium," the Acndium [ov Schistocerca) amencana, Drury, 

 gives a very good idea of the appearance of the specimens sent me from 

 Buenos Ayres, and especially of the quadrate fuscous markings on the 

 upper wings. 



American Acridium. — Acridium (Schistocerca) americanum, after Eiley. 



This Locust is one of the migratory kinds of North America, but 

 appears almost to require mention here on account of its great 

 resemblance (or, as some consider, its probable identity) with the 

 A. peregrinum, the migratory Locust of North Africa and S. Western 

 Asia, which species is also so exceedingly similar to the A. paranevse, 

 entered on in the preceding pages, as to make it doubtful whether these 

 also may not be mere varieties of one species. 



In the 'First Eeport of the U.S.A. Entomological Commission,' 

 p. 37, it is noted, in observations of this North American Acndium, 

 " that one of the most destructive migratory species of South- Westei'n 

 Asia and Northern Africa (Acridium peregrinum) is not only congeneric 

 with this species, but so closely resembles it that ordinary observation 

 would scarcely detect the differences between the two." And (con- 

 tinuing the records of similarity) various writers are of opinion that 

 this Acridium peregrinum does not really differ from tlie A. paranense of 

 the Argentine Eepublic. Thus we have before us the very interesting 



e2 



