14 CONTRIBUTIONS FROM THE NATIONAL HERBARIUM. 
Type in the U. 8. National Herbarium, no. 574253, collected at the Papago Tanks in 
the Pinacate Mountains, Sonora, November 16, 1907, by Dr. D. T. MacDougal (no. 45). 
EXPLANATION OF PLATE 5.—Branch of type specimen. Natural size. 
Elaphrium microphyllum (A. Gray) Rose, N. Amer. Fl. 25%: 250.1911. Puare 6. 
Bursera microphylla A. Gray, Proc. Amer. Acad. 5: 155. 1861. 
Terebinthus microphylla Rose, Contr. Nat. Herb. 10: 120. 1906. 
Type locality, Lower California. 
Hornaday Range, Pinacate Mountains, November 14, 1907, MacDougal 22; slope of 
the Pinacate Mountains, November 20, 1907, MacDougal 55. 
EXPLANATION OF PLATE 6.—From a photograph by Dr. D. T. MacDougal. 
Fouquieria splendens Engelm. in Wisliz. Mem. North. Mex. 98. 1848. 
Type locality, ‘Jornada del Muerto,’’ New Mexico. 
This is illustrated in several plates of the ‘‘Camp-Fires.’’!_ Concerning this charac- 
teristic desert plant Doctor Hornaday writes: ? 
‘There is one other arboreal feature of the deserts which, because of its picturesque 
oddity, I have reserved to the last. It is a product of the plant world unique in 
character, and standing as much apart from related genera and species as does the 
prong-horned antelope among hoofed animals, It is the Ocotillo, the Spanish name of 
which is pronounced o-co-tee’-yo. Next to the giant cactus, it was the most monu- 
mental and picturesque thing of plant growth found by us in two hundred miles of 
fertile deserts. 
“The ocotillo is a multiform tree, and there is nothing else that is at all like it. 
Instead of having a tall main stem and many branches, large and small, it has an 
exceedingly short stem and many very long, wandlike branches. The leaves grow 
all along each branch, from bottom to tip. The stem is a big, thick mass of solid 
wood, all underneath the earth (where the earth has not been blown away), and the top 
of it is large enough to afford holding ground for each branch. From the very limited 
upper surface of the main stem, starting usually at the level of the ground, there rise a 
score or more of long, slender rods of light wood, their bases firmly packed together, 
but otherwise free. They are like slender and very symmetrical fishing rods. As 
they rise they droop outward and spread apart, until they form a group shaped like a 
morning-glory vase. When it is in full leaf, the ocotillo is like a bouquet of green 
wands held at the bottom by an invisible hand. 
‘The stems vary in number from three to seventy-three or even more. I can vouch 
for the last-named number by count. The largest ocotillo that I particularly noted 
had some stems that were, by measurement, eighteen feet long. 
‘‘One of the strangest features of this odd multiple-tree is its leaves and thorns. The 
leaves grow thickly all along the stem, each blade an inch and a half in length. The 
blade springs full-fledged from the upright woody stem, with no free petiole, and its 
color is dark pea green. This profusion of leaves gives each stem of the ocotillo a 
highly pleasing appearance, and denotes water in the not-far-distant yesterday. A 
large ocotillo in full leaf is a beautiful object, and every line of its ensemble bespeaks 
development in a land of queer things. 
‘But mark the transformation. 
‘‘When the last rain has become only a distant memory, when the hungry roots have 
sucked the last drop of moisture from the sandy soil, the hour for the change has 
struck. Fleshy leaves an inch and a half long are far too luxuriant to last long in a 
1 On the plate opposite page 52 several fine specimens are shown, photographed in 
the Ajo Valley 10 miles south of Montezumas Head, Arizona. A young plant in full 
leaf is shown opposite page 80; a plant in full leaf, in color, opposite page 100; an- 
other opposite page 230. 
2 Page 49. 
