376 ENTOMOLOGICAL SOCIETY 



burst upon us in the valley, and rain with blasts of wind obscured 

 the scenery. 



I went to sleep for awhile, and when I awoke, behold the earth 

 had grown green with grass. A refreshing coolness succeeded 

 the hot breath of the desert. The mountains came closer and the 

 valley rose between them, and cultivated fields of alfalfa began to 

 appear. Finally, groves of red-limbed fruit trees, with shining 

 threads of irrigation waters, lined our way, and at sunset the cows 

 came trooping home to the farm yards wading knee deep in clover. 

 This was the end of the desert and the summit of the divide at 

 Beaumont. Thence we whirled downwards in the darkness, 

 passing towns innumerable, with junctions to Pasadena, Redlands, 

 Pomona, and many others, well remembered names. At last we 

 saw the twinkling lights of a great city, and the various stations 

 of Los Angeles were called. 



LETTERS FROM THE SOUTHWEST. 



Salton Lake in the Colorado Desert and Its Insect Fauna. 



BY H. G. HUBBARD. 



YUMA, ARIZ., March 30, 1897. 



In regard to what you say of the insects collected by me in the 

 desert washes at Palm Springs, that the California desert was once 

 an arm of the California gulf, you are surely mistaken. The shells 

 found in all this region are all fresh-water remains ; and the marine 

 shells are found only to the south of the divide which bounds 

 the Salton Sea. The desert sands bordering this depression are 

 white with small shells, but they are all of the usual fresh-water 

 forms. I have preserved a few of the smaller and most abundant 

 forms. I believe even from my short visit to Salton that I 

 have got the essential character of the fauna. It contains abso 

 lutely no marine forms and none at all 'modified by the peculiar 

 environment, except, perhaps, the brine fly (Ephydra), which is 

 quite different from the species inhabiting the Great Salt Lake of 

 Utah. There is no Brine Shrimp (Artemla) in any of the saline 

 springs, and it is very evident that the origin of the saline deposit 

 is quite recent and even now in process of formation from the 

 numerous saline springs which surround the basin both on the 

 north and south. At the surface these springs contain only from 

 i to 6 per cent, of solid saline matter, but at a depth of one or 

 two feet the brine has a density or 27 per cent., consisting of both 

 chloride of sodium and sulphate of soda (Glauber's salt). At 

 no very remote period this basin was filled with fresh water, but 

 neither this nor any other part of the Colorado desert north of the 

 San Jacinto range was ever marine. 



