C. H. TYLER TOWNSEND-BIO-GEOGRAPHY OF TEXAS. 
77 
line is reached at Pratt’s Ranch. Beyond here patches of Transition 
occur all the way to Coyote Spring and beyond, being strongly marked 
for some distance before the latter place. It is left on descending into 
the valley at Springerville, which is on the headwaters of the Colorado 
Chiquito. It does not reappear on the road now until within some ten 
miles of Turkey Tanks, where it sets in for good and continues all the way 
to Flagstaff. It also continues all the way from Flagstaff to Hance’s 
(Canon Springs), except for about ten miles to the north of Cedar Ranch, 
where the road crosses an arm of the Upper Sonoran running in from the 
Painted Desert of the Colorado Chiquito to the east. In this San Fran¬ 
cisco Mountain region there are of course characteristic and true Boreal 
zones on the higher slopes, while a slight Boreal element invades the 
Transition in places. 
I insert here the following diagnosis indicating the interpretation I put 
upon the seven zones which Dr. Merriam has defined in the San Francisco 
Mountain region and Desert of the Little Colorado (N. Am. Fauna, No. 
3, 1890): 
Zones. Dr. Merriam's Belts. 
Arctic Alpine. 
.1. 
Arctic Alpine. 
Hudsonian Alpine.- 
1 2. 
Subalpine or Timberline. 
1 3. 
Hudsonian or Spruce. 
Canadian Alpine. 
.4. 
Canadian or Balsam Fir. 
Transition..- 
i 5. 
Neutral or Pine. 
! 6. 
Pinon. 
Upper Sonoran. 
.7. 
Desert Area. 
In the Grand Canon, at Hance’s, the Transition extends down from 
the top of the east rim (7500 feet above the sea) for about 1500 vertical 
feet, or to a point about 6000 feet above sea, differing according to slope 
exposure. Above this on the edge of the rim, when a north or northeast 
exposure obtains, there occurs a trace of the Boreal. 
Retracing the line to Holbrook, the remainder of the return was by 
another route. The first Transition is met with between Squaw Spring 
and the Wabash Ranch Headquarters, or west-southwest of Jacobs’ Well. 
The next is on the high hills and plateaus east of Zuni, being well 
marked on the hills at Ramah. It continues to Inscription Rock, except 
in the lower open plains, and covers the top of El Moro (Inscription 
Rock) itself, as well as the tops of the many similar high sandstone cliffs 
of that picturesque region. It is entered in earnest at Tenaja, where the 
road goes into the mountains, crossing the crest of the Continental Divide 
and going- down the east slope, and disappears on reaching the mal pais 
or black lava plain which stretches eastward. The last seen of it was in 
the distance on the slopes of Mt. Taylor. 
Gila Headwaters and Black Range Mountains in New Mexico. —In the 
