88 



BULLETIN 56, UNITED STATES NATIONAL MUSEUM. 



Other striking plants of the Dog Mountains arc 

 rupestris (Linnaeus i 



Selaginella 



Spring. 

 Yucca baccata Torrey. 

 Dasylirion sp. 

 Igave palmeri Engelmann. 

 \iilinii liiiilliciineriana (Scbeele) 



Watson. 

 Anemopsis californica Hooker and Ar- 



nott. 

 Argemone mexicana Linnaeus. 

 Fallugia paradoxa (D. Don) Endlicher. 

 Mimosa biuncifera Bentham. 

 Acacia filiculoides (Cavanilles) Tre- 



lease. 

 Acacia constrict a Bentham. 

 cassia wislizeni Gray. 

 Astragalus mollissimus Torrey. 

 Astragalus nuttallianus de Candolle. 

 Krameria' secundiflora de Candolle. 

 Fouquieria splendens Engelmann. 

 Covillea tridentata (de Candolle) 



Vail. 



Jatropha macrorhiza Bentham. 



Rhus irilobata Nuttall. 



Jilt us microphylla Engelmann. 



Zizyphus sp. 



Vitis arizonica Engelmann. 



Circus pectinatus rigidissimus Engel- 

 mann. 



Opuntia lindheimeri Engelmann. 



Opuntia filipendula Engelmann. 



Opuntia arborescens Engelmann. 



Lycium pallidum Miers. 



Anisacanthus thurberi Gray. 



Cucurbita fcetidissima Humboldt, 

 Bonpland, and Knuth. 



Ibervillea lindheimeri (Cognlaux) 

 Greene. 



Baccharis pteronioides de Candolle. 



Baccharis glutinosa Persoon. 



Orassina grandiflora (Nuttall) Kuntze. 



Perez i a nana (J ray. 



Tri.ris angustifolia de Candolle. 



Station No. 16. — Whitewater. Chihuahua, Mexico. This camp 

 was located on the south side of an arroyo, in which a shallow well 

 supplied us with very bad water, about a mile south of Monument 

 No. 61 and 240 kilometers (153 miles) from the Rio Grande, at an 

 altitude of 1,528 meters (5,013 feet), in the midst of the Whitewater 

 Hills, between the East and West Playas. In September, 1893, the 

 Whitewater arroyo contained water. Animal and plant life were 

 abundant, and large collections were made. I occupied this station 

 .May 30 and 31, June 2 and 3, June 13 to 22 and 27 to 29, 1892; Sep- 

 tember 10 to 15 and 23, 1893. Mr. Holzner was there June 13 to 22 

 and 27 to 29, 1892. 



Vegetation. — There were no forests in the immediate vicinity of 

 the station, the only trees being small mesquites and a few straggling 

 oaks, hackberry, mulberry, and wild china trees, together with the 

 desert yucca. On the neighboring East Playas and West Playas 

 valleys wore extensive tracts occupied by mimosa and creosote bushes, 

 with the tapioca {Jatropha macrorhiza Bentham) and several kinds 

 of gourd {Cucurbita fcetidissima Humboldt, Bonpland, and Kunth; 

 C. digitata Gray; Apodanthera undulata Gray, and a species of 

 Ibervillea) in abundance. The plain and grassy hills surrounding 

 "White Water abound with aloe. Nolina or bear-grass, Dasylirion, 

 yucca, acacia, senna, sumach, Fallugia, Triasis, and numerous species 

 of cacti, among which are Opuntia macrocentra Engelmann, 0. arbor- 

 escens Engelmann. and the beautiful rainbow cactus {Cereus pecti- 

 ii, it us rigidissimus Engelmann. 



