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J. A. G. REHN 



subfamily Is found a wide range of structural modifications and de- 

 velopments, and adaptations to conditions ranging from those of 

 the densest of lowland rain-forest undergrowth to the most arid 

 desert environments. In my opinion the subfamily is clearly one of 

 Neotropical development. Its members occur over the Americas 

 from the Dakotas to central Argentina and Chile, with a single 

 endemic genus on one island (Cuba) of the West Indies. 



Within the territory we are covering five genera of the subfamily 

 occur, one of which, Brachystola, sweeps north broadly from Mexico 

 over the Great Plains to South Dakota, and also is locally abundant 

 in central and southern Arizona; another, Taeniopoda, is narrowly 

 intrusive from Mexico and Central America, where the genus is 

 broadly developed, in border areas of the United States from 

 western Texas to central-southern Arizona; a third, Phrynotettix, 

 is an inhabitant of Sonoran deserts, brushland, hills, and mountains, 

 from western Texas to south-central Arizona, and also extends 

 southward in non-tropical Mexico; a fourth genus Tytthotyle, is 

 reported from the hottest and most arid Lower Sonoran deserts of 

 southwestern Arizona, southern Nevada, extreme southwestern 

 Utah, and southern California, although it doubtless occurs in suit- 

 able sections of Sonora and perhaps Baja California; while the 

 fifth genus, Dracotettix, is known only from the coastal ranges, 

 the San Gabriel and San Bernardino Mountains, the lower and 

 drier eastern slopes of the southern Sierras, the Panamint Range, 

 and other desert mountains of southern California, as well as extreme 

 northern Baja California, where the most generalized member of 

 the genus has been found. 



The broad center of origin of our Romaleinae has clearly been the 

 Neotropical Region, but the genera in western North America have 

 doubtless developed as generic entities in our territory and in Mexico 

 (particularly in northern Mexico); only one of the genera, 

 Taeniopoda, extends as far south as Panama and none is represented 

 in South America. Romalea, the sixth genus of this subfamily, in 

 North America, is limited to the southeastern United States, ranging 

 only as far west as central Texas and not entering semi-arid country. 

 It would appear that the North American genera of the subfamily 

 indicate a number of incursions from the south, of which the first is 

 now represented by Romalea. The ancestral line of Romalea probably 

 entered the area at least as early as the Pliocene. Dracotettix, con- 



