C. H. TYLER TOWNSEND — BIOGEOGRAPHY OF MEXICO, ETC. 
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near to townsendi, that Professor Cockerell has described it as a variety 
of that species, var. plucheae n. var. It was not confined to the base of 
the plants, which are rather tall growing, bnt occnrred well np the 
stalks as well. 
Dactylopius gutierreziae Ckll. — On the leaves of Gutierrezia sarothrae, 
Blazer’s Mill, 6200 feet, October 2. A new species, with a long white 
ovisac which takes np the whole width of the narrow leaves of the plant. 
Also found abundantly all over the mesa to the west of the Organ 
Mountains, on a variety of the same plant. 
Orthezia nigrocincta Ckll. — Found plentifully at Blazer’s Mill, on 
same plants with the preceding. This was originally found by me in the 
canon of the Gila, at Gila Hot Springs, 1ST. M., in 1894. 
Aleurodes berbericola Ckll. — A new species, found on Berberis , Blazer’s 
Mill, 6200 feet, October 2. 
CAPITAL MOUNTAINS. — The plains at the base of the Capitan 
Mountains are probably about 5000 feet elevation, though this is only 
an estimate. The Capitans rise probably to about 8000 or 9000 feet. 
They are Transition , except the lower portions around the base. There 
is not more than a touch of the Boreal on their highest portions, so far 
as could he judged at a distance of half way up their sides. 
WHITE SANDS. — On the northwestern part of the Tularosa plains, 
there lies a remarkable piece of country known as the White Sands, far 
greater in extent than any similar formation known to me in the south- 
west. These sands are pure gypsum, and are raised up in hanks and 
drifts, often to a height of fifty feet above the level of the surrounding 
plain. They extend over an area some forty miles long, by perhaps an 
average of ten miles in width. They lie just to the east of the San An- 
dreas range, and immediately to the west of the wagon road from Las 
Cruces to Tularosa, which skirts their edge for some ten miles. The 
gypsum is nearly white — creamy white — in color, the hanks appearing 
from a little distance almost like snowbanks shining in the sun. The 
texture is not powder-like and dusty, hut rather sand-like, though mod- 
erately firm, and does not greatly impede walking; nor does it stick to 
the shoes or clothing, being easily brushed off. It is simply disintegrat- 
ed and weathered gypsum. From well up in the Sacramento Mountains 
— as high up on the road from Tularosa to the Agency as one can go 
before losing sight of this part of the plain — this immense stretch of 
sand lies spread out before the eye in a panorama of billows, exactly 
resembling a large area of high surf breaking on a sandy shore. The 
mountains on the farther side seem like a continuation of the land in 
a promontory, or rocky coast-line. It is a. magnificent sight, and one that 
