March. 1904. Mammals of Southern California — Elliot. 275 



gravelly soil about creosote bushes; but no specimens of Dipodomys 

 m. simiolus were seen, and the animal appeared to be entirely absent 

 from the region. 



From this place, proceeding northward, Mr. Heller's next camp 

 was at Lone Willow Springs, in the Panamint Valley. This last 

 "lies at an elevation of 1,200 feet between the Slate and Argus 

 Mountains on the west and the Panamint Range on the east. It is 

 a long, narrow vallev extending north and south without outlet, its 

 lowest part being occupied by an alkaline marsh, which is usually 

 dry. The sides of the lake are in some places vertical walls, which 

 show traces of wave action, and are occasionally made up of fossil 

 mollusca, or more commonly show traces of cavities where such 

 fossils existed. It is evident that the valley was very recently an 

 inland sea or lake. The physical features are identical with those 

 of Death Vallev, of which it is a prototype at a somewhat higher 

 elevation." Collections in this valley were made in two places, 

 Lone Willow Springs and Ballarat, the first being at the southern 

 end, in the Slate Range, at an altitude of 2,500 feet. "The country 

 about the Spring is broken by numerous small washes and rock 

 ledges, with the creosote most abundant on the hillsides, while the 

 mesquite and cacti occur about the rocky places. Ballarat is on the 

 eastern side of the valley and at the head of the alkali marsh. The 

 Lower Sonoran Zone covers the vallev and the hills to an altitude 

 of 7,000 feet above the sea." A short stay only was made at these 

 places and only a few mammals were taken. The soil in the valley 

 is extremelv dry, and in consequence of this no species of Thomomys 

 is found there, although they occur in the canons and on the summits 

 of the mountains. 



From Ballarat Mr. Heller passed through Emigrant Pass to 

 Mesquite Valley, which is "in the northern end of Death Valley 

 and slopes gradually to the south, but all of its surface is above sea 

 level. Death Valley lies between the Panamint Range on the 

 west and the Funeral and Grapevine Ranges on the east. It has a 

 general northwest and southeast direction, attaining an extreme 

 length of about 120 miles and a maximum width of fifteen miles. 

 Death Valley proper comprises the southern third part, and consists 

 almost wholly of an extensive alkaline or borax marsh, the whole 

 of which is more than 100 feet below sea level. The lowest depres- 

 sions in this marsh are 480 feet below sea level. Employing the 

 lowest level as a base, we would have the Panamint Range reaching 

 a height of over 11,000 feet and the Funeral Mountains of about 

 7,000 feet. The marsh is snowy white in appearance, being covered 



