MAMMALS OF THE MEXICAN BOUNDARY. 



87 



{Cereus peel 'mat us rigidissimus Engelmann), the range of which 

 extends west to the Pajaritos Mountains. 



Station No. 15. — Dog Spring, Grant County, New Mexico. This 

 splendid spring is about 2 kilometers ( 1 j miles) north of Monument 

 No. 55, and has an altitude of 1,475 meters (4,839 feet). It is near 

 the south extremity of the Dog Mountains, a rugged range of which 

 Emory Peak-, having an altitude of 1,868 meters (6,129 feet), is the 

 highest. The drainage is toward the Corralitos River, the lowest 

 point surveyed, 6.4 kilometers (4 miles) southeast of Dog Spring, 

 Inning an altitude of 1,350 meters (4,430 feet). The increase of 

 arboreal vegetation became apparent as Ave approached this camp 

 from the eastward. The oak. sycamore, walnut, and mulberry were 

 here first met with. Checkerbark juniper crowned the summits of 

 the Dog Mountains, and descended to the foot in a few of the narrow 

 canyons. I camped at Dog Spring from May 21 to 30 and June 3 to 

 13, 1802, and from September 15 to 23, 1893; Mr. Holzner from May 

 25 to June 13, 1892. The arroyo extending from Dog Spring to the 

 Corralitos River marks the western extension of several mammals of 

 the Eastern Desert. Extensive collections were made at this camp 

 and in the adjacent Dog Mountains. Leaving the bottom of the 

 valley at our camp and proceeding toward Emory Peak, the ground 

 was everywhere strewn with fragments of chalcedony, many of which 

 had been pasted as ornaments in the cement walls of ancient cliff 

 dwellings by the aboriginal builders. The mountains are largely 

 of rhyolite and hornblende-mica-andesite, the rock being often strik- 

 ingly colored. 



Flora of Dog Mountains.' 1 — Here large collections were made and 

 the following lists show the principal varieties of plant life found: 



The trees are: 



Pin us cembroides Zucearini. 



Juniperus monosperma (Engelmann) 

 Sargent 



Juniperus pachyphlcea Torrey. 



Juglans rupestris Engelmann. 



Yucca constricta Buckley. 



Salix nigra Marshall. 



Salix occidentalis longipes (Anders- 

 son) Bebb. 



Populus fremontii Watson. 



Populus angustifolia James. 



Quercus oblongifolia Torrey. 



Quercus arizonica Sargent. 



Quercus emoryi Torrey. 



Celt is occidentalis Linmeus. 



Morns celtidifolia Humboldt, Home- 

 land, and Kunlli. 



Platanus wrightii Watson. 



( 'ercocarpus parvifolius paucidentatus 

 Watson. 



Prosopis glandulosa Torrey. 



Ka berlinia spinosa Zuccarini. 



Sapindus marginatus Willdenow. 



Arbutus arizonica (Gray) Sargent. 



Bumelia rigida (Cray) Small. 



I' ni. tin us relit Punt Torrey. 



CMlopsis linearis < ( 'a vanillos i Sweet. 



"These mountains are sparsely wooded and of the roughesl description. On 

 the east side they are furrowed by canyons with jagged, precipitous sides 

 abounding in eaves and erosions. The average beigbl of i he higher peaks is 

 nearly 1,829 meters (6,000 l'eet). 



