MAMMALS OF THE MEXICAN BOUNDARY. 9 



Texas, where the greater part of the following day was spent by 

 Mr. Holzner and myself in examining the country and collecting 

 mollusks and birds on the South Fork of Trinity River. 



The forests of Indian Territory and the adjacent portion of Texas 

 through which we passed in going to Fort Worth are largely of oak, 

 with many elms along the streams; and, in fact, the arborescent 

 vegetation is quite varied, though Juniperus vh'giniana was the 

 only conifer noticed. Sycamores and cottonwoocls were locally 

 abundant; and the common mistletoe {Phoradendron favescens Nut- 

 tall) was frequently noted, from the Red River crossing southward, 

 especially upon the elm. The first prickly-pears {Opuntia) were seen 

 at Fort Worth. As our train proceeded from Fort Worth toward 

 El Paso, Texas, red junipers and other timber similar to that in 

 Indian Territory and northern Texas, were seen for several hours; 

 then a more desert-like region was reached near the Brazos River. 

 Yuccas and arborescent opuntias, creosote bushes (CoHUea), and 

 other western desert plants appeared and increased in numbers. 



Fehi'uary 1 to March 14, 1892. — We arrived at El Paso, Texas, on 

 February 1, and there remained until March 14. During this time I 

 was quartered in the city. Daily trips were made to the surrounding 

 country, and mammal trapping and bird 'collecting were systemat- 

 ically carried on. Excursions were made to Juarez, on the Mexican 

 side of the Rio Grande, to the Franklin Mountains, and down to the 

 cultivated lands about Ysleta on the Texas side of the river. After 

 February 17, on which date Mr. Holzner moved to the first camp 

 of the surveying party, on the east bank of the Rio Grande opposite 

 to the initial monument of the survey, I made daily visits to that 

 camp. 



March 1^ to iJ, 1892. — Broke camp on the east side of the Rio 

 Grande and crossed on the bridge from El Paso to Juarez, then pass- 

 ing up the west shore of the Rio Grande and making camp opposite 

 old Fort Bliss, Texas. 



March 15 to 20, 1892. — On the way to Monument No. 15, across a 

 plateau about 1,250 meters (4,101 feet) above sea level, and about 

 100 meters (328 feet) higher than the Rio Grande at the initial 

 monument. This plateau is described as a desert; but, though dry, 

 it is productive. The eastern half is covered with sandhills, built 

 up bv the low mesquite, sagebrush, and yucca. Near the middle of 

 this tract, which measures about 80 kilometers, or 50 miles on the 

 boundary, were seen two juniper trees {Junipeims monosperma) from 

 which we took specimens. 



Parosela scoparia (Gray) Heller is a very characteristic shrub of 

 this desert. The western half is covered with a black grama grass 

 LBouteloua eriopoda Torrey). Here and there large patches of the 

 gregarious creosote bush {Covillea tridentata) were seen and smaller 



