SPECIES OF LOCUSTS 309 



and collaborators (1932) may be mentioned. In the latter work 

 an illustrated account of the phases and their chief characteristics 

 will be found. Very little definite information is available as to 

 the permanent breeding grounds of this species owing to the vast 

 extent and difficult nature of the countries wherein they are 

 believed to be located. A good deal of evidence points to the 

 source of recent outbreaks as being in lands bordering the Red 

 Sea (Sudanese-Arabian region). The localisation of these breeding 

 grounds by aerial surveys and other means is one of the most 

 important of the schemes now being undertaken by international 

 arrangement regarding anti-locust investigation. 



3. The Moroccan Locust (Dociostaurus maroccanus Thnb.). 



Phasis gregaria = maroccanus Thnb. 



Phasis transiens = degeneratus Brnov. 

 The area of distribution of this locust comprises dry, hilly, and 

 upland regions of those countries which form the Mediterranean 

 littoral and the greater part of Southern Russia. Its permanent 

 breeding grounds are the stony slopes of mountains and hills 

 where vegetation is somewhat scanty. From these regions 

 swarms invade the plains of neighbouring territory and the insect 

 is more especially prevalent in Spain, Cyprus, Transcaucasia and 

 Turkestan. 



4. The South American Locust (Schistocerca paranensis 'Burm.). 



Phasis gregaria = paranensis Burm. 



Phasis solitaria = ? americana F. 

 Knowledge of South American locusts is still very incomplete, 

 and it has been claimed that several species are involved, but 

 the evidence on the whole points to there being only one of 

 true migratory habits. It is further probable that the North 

 American species S. americana is only the solitary phase of the 

 locust under consideration. The ^range of the South American 

 locust is from Argentina north of the fortieth parallel up 

 through parts of Brazil to Venezuela and Central America. 

 Migrating swarms further extend to Mexico and the West 

 Indies. Relatively little is known as to its bionomics and 

 periodicity, and its breeding grounds have not so far been 

 located. 



