C. H. TYLER TOWNSEND-BIO-GEOGRAPHY OF TEXAS. 
79 
Gila Hot Springs, and from there up the East Fork the Transition obtains 
on the crests of the hills and ridges. It does not extend so far down the 
sides of the canon in the East Fork as in the West Fork. For about five 
miles before reaching the D D Bar ranch, the country is more open and 
the Transition nearly or quite disappears. 
Above there it stretches from the Tongue of Land to the basin of the V 
Cross T Ranch. Then immediately to the east of this ranch, it begins 
abruptly in the steep sides of the Black Range Mountains, and continues 
down Corduroy Canon to its outlet upon the plain. It is entered again 
on climbing the hill or ridge about two miles up the east draw on the 
left hand side, and here in July, 1894, was one of the most beautiful 
stretches of country that I ever remember seeing. The rolling, park¬ 
like country was carpeted with newly grown green grass about two inches 
long, and looked like a well kept lawn, while graceful pines stood here 
and there or congregated in clumps. The Transition continues now un¬ 
til shortly before reaching Fairview. Immediately beyond the last 
named place it is crossed again in a not very high range of mountains, 
and again left on entering the plain below. The last seen of it is on the 
spurs of the latter mountains. There is little or no trace of the Boreal 
in the Black Range where we crossed. 
Organ Mountains , New Mexico. —In Science for December 8, 1893, pp. 
313-315, I outlined five very well marked vertical life belts in the 
flora of the region, which occur between the Rio Grande at Mesilla, 
N. M., and the peaks "of the Organ Mountains about fifteen miles 
to the eastward. Of these, as there defined, the two called “ juni¬ 
per or cedar” and “pine” represent the Transition , with a touch 
of the Boreal. The “pine” belt, as there described, should be 
split into “Pine belt,” 7500 to 8000 feet (west and south slopes), with 
Pinusponderosa as characteristic; and “Fir belt,” 8000 feet, and over, with 
Pseudotsuga douglasii as almost sole representative. Of the plants men¬ 
tioned on northeast slope, Nos. 13 (P. edulis) to 15 inclusive, 6200 to 
7000 feet, belong to Juniper belt; and 16 to 17, 7000 feet (top of ridge), 
to Pine belt. 
The tops of the peaks (8800 feet) are bare rock, with no soil for five 
to eight hundred feet. Not only does the Douglas fir on the highest 
ridges and slopes indicate the presence of the Boreal, but this is borne 
out by the former occurrence of the mammalian genera Ursus and Ovis. 
Various Localities in New Mexico. —The San Andres Mountains, 
stretching northward from the north end of the Organs, have the Transi¬ 
tion on their higher portions. It is a low range. 
The Sacramento Mountains, across the San Augustine plain northeast 
from the Organs, have the Transition well marked, with also a good 
touch of the Boreal. Ursus abounds, and deer, trout, and turkeys are 
