58 
TRANSACTIONS OF THE TEXAS ACADEMY OF SCIENCE. 
will repay the discomforts of traveling far to see. In effect it is veri- 
tably a sea of snrf turned to gypsum. When one comes to walk over a 
portion of it, and examine its contours in detail, he finds the waves and 
billows, the crests and troughs, the heaving swells and profound hollows 
— all true to the outlines exhibited by a heavy sea. Such an extent of 
country must have a peculiar fauna and flora, so far as there is a possi- 
bility of life existing upon it — and plenty of life exists there. The 
whole region is scatteringly covered with vegetation — such vegetation 
as can maintain itself. There are many flowers at certain seasons after 
rains — in October, for instance — and these flowers are visited by many 
hymenoptera, diptera, etc. Other insects frequent the vegetation and 
the sands — mutillids, coleoptera, etc. Ho collecting has ever been done 
here, except a half hour of work by the writer, late in the afternoon of 
October 6, 1896; during which an area of not more than 100 yards 
diameter was traversed, situated just in the edge of the tract, next the 
road at the holes known as Whitewater. These holes sometimes have a 
little saline water in them, but are more often dry. There is often good 
water, however, just a little further on, over the edge of the sands. It 
is seven miles from Whitewater to Lunas Well (Pelman’s), wnich is 
really the nearest water that can be depended on. The elevation of the 
plain here at the edge of the White Sands is probably about 4000 feet. 
Whitewater is at the southeastern edge of the White Sands, and about 
thirty miles from Tularosa. It may be mentioned here that what I have 
called the Tularosa plains are sometimes called the San Augustine plains ; 
they extend north from the Organ Mountains to White Mountain, and 
extend down east of the Organs to the Texas- boundary. 
Kemarks on the Fauna. — The writer found on these sands a small 
lizard of the same whitish color as the gypsum, but unfortunately the 
few specimens seen escaped capture. Two. whitish spiders, one of 
them an attid, were taken on vegetation on the sands, and 
have been determined by the Department of Agriculture. They 
are doubtless peculiar to the sands. The attid is Habrocestum n. sp.; 
it was chalk-white, speckled with black. The other, Philodromus 
sp.?, had the abdomen chalk- white with pale reddish-brown markings, 
rest of body being greenish-white. These notes were made from the 
fresh specimens by Professor Cockerell. Several bushy clumps of Bige- 
lovia graveolens var. appendiculata Eastw. n. var., just beginning to 
flower, yielded numerous specimens of a new bee of the genus Perdita, 
which Professor Cockerell has named Perdita townsendi. “ It is nearest 
to P. bigeloviae, but quite distinct, especially in the male.” (Ckll.). An- 
other bee, a larger form, belonging to the genus Collates, was taken with 
the Perdita on the same flowers, and was at first supposed to be the same 
