16 CONTRIBUTIONS FROM THE NATIONAL HERBARIUM. 
Lemaireocereus thurberi (Engelm.) Britton & Rose, Contr. Nat. Herb. 10: 426. 
1909. 
Cereus thurberi Engelm. Amer. Journ. Sci. II. 17: 234. 1854. 
Type locality, ‘‘Canyon near the mountain pass Bachuachi.” 
A living specimen and fruit were collected at Sonoyta, Sonora, and sent to Wash- 
ington. A fine colored illustration of this species is given by Doctor Hornaday.' The 
plant illustrated had 22 stems, the tallest being 20 feet high. The species was first 
seen at Sierra Blanca and last at the Ajo mines, Arizona, at about the same latitude as 
Tucson, and these may be considered as the northern limits for the species. 
Lophocereus schottii (Engelm.) Britton & Rose, Contr. Nat. Herb, 12: 427. 1909. 
Cereus schottit Engelm. Proc. Amer. Acad. 8: 288. 1856. 
Pilocereus schottti Lem. Rev. Hort. 1862: 428. 1862. 
Type locality, “Toward Santa Magdalena,’’ Sonora, Mexico. 
A living specimen was collected at Sonoyta, Sonora, and sent to Washington. 
Mamillaria grahami Engelm. Proc. Amer. Acad. 3: 262. 1856. 
Type locality, ‘Mountains from El Paso southward and westward to the Gila and 
Colorado, and up the latter river.’’ 
Living specimens were collected on the Pinacate Mountains and sent to Washington. 
Opuntia bigelovii Engelm. Proc. Amer. Acad. 3: 307. 1856. Prare 10. 
Type locality, “On Williams River’’ (Bill Williams River), Arizona. 
Common on Hornaday Mountain, Sonora. 
EXPLANATION OF PLATE 10,—From photograph by Dr. D. 'T. MacDougal. 
Opuntia chlorotica Engelm. & Bigel. Proc. Amer. Acad. 3: 291. 1856. 
Type locality, “From San Francisco Mountains to Mojave Creek,” Arizona. | 
Near summit of Pinacate Mountains, MacDougal. 
Opuntia fulgida Engelm. Proc, Amer. Acad. 8: 306. 1856. 
Type locality, “ Mountains of western Sonora,’’ Mexico. 
Sonoyta, Sonora, MacDougal. 
Philibertella hartwegii heterophylla (Engelm.) Vail, Bull. Torrey Club 24: 308. 
1897. 
Sarcostemma heterophylla Engelm. in Torr. U. 8. Rep. Expl. Miss. Pacif. 5: 362. 
1856. 
Type locality, “Near Fort Yuma,’’ Arizona. 
Walls Well, Ajo Mountains, Arizona, November 7, 1907, MacDougal 7. 
Cuscuta californica Choisy, Mem. Soc. Phys. Hist. Nat. Gendve 9: 279. 1841. 
Type locality, “Nov. [am] Californiam.”’ — 
MacDougal Crater, Pinacate Mountains, November 14, 1907, MacDougal 26. The 
immature plants are growing on Kallstroemia grandiflora. 
Euploca aurea Rose & Standley, sp. nov. PLATE 11, 
Low, much branched annual, 30 cm. high or less; branches spreading, stout, 
hirsute; leaves oblong to elliptic or oval, thick, yellowish green, hirsute, small, 
mostly about 1 cm. Jong, acutish, rounded at the base, all on short, stout petioles 
one-third as long as the blades; flowers axillary, scattered; lobes of the calyx linear- 
subulate, strigose; corolla bright yellow, the limb about 6 mm. wide, the throat some- 
what inflated; style long and slender; stigma penicillate; achenes 2, hemispherical, 
each finally splitting into 2, strigillose, smooth. 
Type in the U. S. National Herbarium, no. 574265, collected on sand hills near 
Adair Bay, Gulf of California, November 20, 1907, by Mr. G. Sykes (no. 61). 
This is not closely related to any other species of the genus, being distinguished 
chiefly by its yellow corollas and bristling indumentum. 
EXPLANATION OF PLATE 11.—a, Branch of type; b, calyx lobe. a, Natural size; b, scale 4. 
' “Camp-Fires,’’ facing page 136. 
