1915.] NATURAL SCIENCES OF PHILADELPHIA. 365 



I. The Deagoon Mountains. 



This range stands 25 or 30 miles west of the Chiricahua Mountains 

 in Cochise County, Arizona. The well-known double-headed peak 

 of Dos Cabezas is seen northeastward and the Whetstone Mountains 

 westward, but the Dragoons are entirely isolated from other ranges. 

 The Pearce mining district lies on the east side. To its proximity 

 and the demand for mine timber the deforestation of the mountains 

 is due. All of the timber was cut about 25 years ago, but the 

 range, now forming the Dragoon Forest Reserve, shows good repro- 

 duction in places. At present the mountains are almost as bare 

 as the Dos Cabezas. 



The range is reached from Dragoon Summit, a station on the 

 Southern Pacific R. R. at the northwestern foot of the mountains. 

 North of the railroad the "Little Dragoons" form a low continuation 

 of the range. There is a depression at Middle Pass (Middlemarch 

 Canyon), where a road from Tombstone to Pearce crosses the range. 

 We did not explore the southern half of the range, below Middle- 

 march, nor the Little Dragoons north of the railroad. 



The mountains are formed of a complex of limestones and igneous 

 rock, the granites forming wild labyrinths of narrow gorges abounding 

 in cliffs and falls, separated by inaccessible crags and spires, which 

 gave a refuge to the Apaches thirty or forty years ago. The lime- 

 stones, forming a large part of the range, are accessible enough, 

 though rather abrupt, and as usual they proved much more prolific 

 of snails than the granitic and andesitic rocks. 



The range was visited by us (Ferriss, Daniels and Pilsbr}^) in 

 October, 1910. A week was spent in Tweed Canyon, where there is 

 a small stream. The map (p. 366) showing collecting stations from 

 Stations 7 and 8 northward was sketched from high points around 

 Tweed Canyon and its northern amphitheatre. After Pilsbry had 

 left, Ferriss and Daniels moved south to Middlemarch Canyon, 

 and the stations (28-36) south of Station 8 are located by notes 

 and a sketch made by them.- 



2 The map is intended solely to show the positions of our collecting stations, 

 many of which can probably be located exactly, and the others approximately, 

 by the landmarks given. The contour lines merely show local relative elevation, 

 not absolute altitude, and are not consistent on different parts of the map. 

 The summit midway between Stations .5 and 12 on the northern ridge of the 

 amphitheatre above Tweed Canyon is visible from the railroad at Dragoon 

 ■Summit. 



