ECHINOCEREUS. 
41 
Figure 51 is from a photograph of a plant 
collected by Dr. Rose on the Sierra Blanca, 
Texas, in 1913; figure 52 shows a flower and 
figure 53 a fruit copied from the above cited 
illustrations in the Cactaceae of the Mexican 
Boundary Survey. 
57 . Echinocereus barthelowanus sp. nov. 
Plants cespitose, forming large clusters; stems 
cylindric, 1 to 2 dm. long, 4 to 5 cm. in diameter; 
ribs about 10, somewhat tuberculate below, but 
completely hidden by the stout numerous spines; 
areoles approximate, 2 to 5 mm. apart, white- 
felted when young; spines numerous, acicular, 
sometimes 7 cm. long, pinkish when quite young, 
afterward white or yellow with brown or blackish 
tips, in age becoming gray; flowers only 10 to 12 
mm. long; perianth-segments oblong, 3 to 4 mm. 
long, ovary minute, strongly tubercled, hidden 
under the mass of spines; spine-clusters on ovary 
with 6 to 12 white or pinkish tipped spines, half as long as the flower. 
Collected by J. N. Rose on the mesa, near Santa Maria Bay, Lower California, 
March 18, 1911 (No. 16278). Here we would refer also plants collected by C. R. Orcutt 
near the same locality in 1917. 
The species is named for Captain Benjamin Barthelow, in whose company Dr. Rose 
collected the plant while making a cruise in 
Steamer Albatross in 1911. 
58 . Echinocereus mamillatus (Engelmann). 
Cereus mamillatus Engelmann in Coulter, 
Contr. U. S. Nat. Herb. 3: 405. 1896. 
Cespitose; stems ascending, 2 to 3 dm. long, 
cylindric, 3.5 to 6 cm. in diameter; ribs 20 to 25, 
sometimes oblique, strongly tuberculate; spines 
white or pinkish; radial spines 10 to 25, acicular, 
3 to 12 mm. long; central spines 3 or 4, much 
stouter than the radials, 1 to 2.5 cm. long; flowers 
and fruit unknown. 
Type locality: Mountain sides south of Mulege, Lower California. 
Distribution: Southern Lower California. 
Illustration: Sehelle, Handb. Kakteenk. 97. f. 36, as Cereus mamillatus. 
Figure 54 is from a photograph of a plant sent to the New York Botanical Garden 
from the Missouri Botanical Garden, in 1904. 
59 . Echinocereus ehrenbergii (Pfeiffer) Riimpler in Forster, Handb. Cact. ed. 2. 775. 1885. 
Cereus ehrenbergii Pfeiffer, Allg. Gartenz. 8: 282. 1840. 
Cespitose, 2 dm. high; joints often procumbent, pale or leaf-green; ribs 6, obtuse, sinuate, 
areoles remote, 2 cm. apart, white-felted; radial spines 8 to 10, slender, white; central spines 3 or 4, 
yellowish at base; flowers not known. 
Type locality: Not cited. 
Distribution: Central Mexico. 
A living plant was obtained for the New York Botanical Garden from M. Simon of St. 
Ouen, Paris, in 1901, but it died before flowering. 
the Lower California waters on the U. S. 
Figs. 52 and 53.—Flower and fruit of Echinocereus 
stramineus. X0.25. 
