40 " BULLETIN 56, UNITED STATES NATIONAL MUSEUM. 



extends down to 1,830 meters (6,000 feet) altitude. It was not found 

 on any other mountains of the boundary strip. I loolved for it in 

 vain on the San Jose Mountains, where, in the upper zone, occupied by 

 the Gambel oak, Mexican white pine, and aspen, it is rephiced by the 

 Avhite fir. In ascending the San Luis Mountains by way of Turkey 

 Canyon, the first Douglas spruce is reached at 1,800 meters (0,100 

 feet) ; the next at 1,81)0 meters (0,200 feet). In Millers Canyon of 

 the Huachuca Mountains this spruce begins at 1,830 meters (0,000 

 feet), which is the lowest point at which it was noted. In both of 

 these mountains the lowest Douglas spruces w^ere found associated 

 with Pinus chihuahua na and Acer saccharum (jrandidentatuni. In 

 1887, I measured one of these trees in the camp at Little Springs, at 

 the north base of San Francisco Mountains (altitude 2,500 meters, or 

 8,250 feet), and found it to be 3.3 meters (10.8 feet) in circumference 

 and 33.5 meters (110 feet) in height. 



ABIES CONCOLOR (Gordon) Parry. 

 WHITE FIR. 



This tree is very rare in the Huachuca Mountains. A few Avere also 

 found in the San Jose Mountains. A specimen from the last place 

 was identified by Prof. Charles. S. Sargent. It Avas not found 

 elsewhere on the INIexican Boundary Line, but is common in several 

 localities along the Grand CauA^JU of the Colorado, in northern 

 Arizona. 



TAXODIUM DISTICHUM (Linnaeus) Richard. 

 BALD CYPRESS. 



The range of the bald cypress includes the lower Rio Grande 

 vallev. In traveling east on the Southern Pacific Railroad it is 

 first seen at Sabinal, Texas. It extends far up the valley of the 

 Nueces, a few trees having been found between the Nueces and 

 Devils rivers. 



LIBOCEDRUS DECURRENS Torrey. 

 INCENSE CEDAR. 



We found a few of these trees on the Laguna Mountains of the 

 Coast Range, near Campbell's Ranch, at the altitude of about 1,525 

 meters (5,000 feet). Sargent states that this magnificent tree reaches 

 100 to 150 feet in height and 7 to 8 fe^t in diameter of trunk. 



CUPRESSUS GOVENIANA Gordon. 

 GOWEN CYPRESS. 



This cypress was only found in the Jamul Valley, between El Nido 

 and Dulzura, in San Diego County, California. 



