562 ENTOMOLOGICAL NEWS. [October, 



The timber is confined to the ranges and water-courses, while 

 scattered growths of mesquite and palo-verde cover the foot- 

 hills and isolated places on the plains. 



Leaving the cultivated portion of the valley, we see the true 

 character of the country ; long level stretches covered with 

 grease-wood under whose shelter many rare and delicate forms 

 of plant life grow. 



As the country becomes more broken we reach the cacti zone 

 where we find ourselves in a veritable forest of these curiosities 

 of plant life. 



Yuccas, an occasional pine and stunted oaks appear, but all 

 about you denotes the absence of the one great factor for the 

 welfare of this wonderful country — water. 



The rains come at last, the desert blossoms, and with the 

 flowers come the insects, showing us a wealth of life that is 

 truly wonderful. 



Thus in brief we have an idea of the physical condition of 

 the country. 



The principal town of the region is Phoenix ; in making our 

 collecting excursions it was our headquarters. Being a dry 

 season, with about one-tenth of an inch of rain in ten months, 

 and most of the collecting done from October to May, the con- 

 ditions were not favorable to represent the fauna, but the series 

 gives an idea of its extent. 



As will be seen by the subjoined li.st, there is commingling 

 of the fauna of the North with the Sonoran fauna of Mexico. 



As civilization advances, and larger areas of desert lands are 

 reclaimed by irrigation, climatic changes will take place, forcing 

 the desert fauna to recede southward or become extinct, so that 

 collections made in future years will .show marked changes from 

 those recorded by LeConte, Horn, Hubbard, Schwarz, Wick- 

 ham and others. 



Of the immediate habits of the insects little is known except 

 of such forms as occur elsewhere. Cvll<'nc onlnniatns and Tro- 

 jrosita viresccns inhal)it the mesquite and prove very destructive. 



In the most barren part of the desert we find Edrotcs ventri- 

 cosus, which arc always in a hurry, though only to be found in 

 the early hours, hiding in their burrows during the heat of 

 mid-day. 



