STAISTDLEY TREES AND SHRUBS OF MEXICO. 521 



7. Fagonia barclayana' (Benth.) Rydb. N. Amer. Fl. 25: 104. 1910. 

 Fagonia californica barclayana Benth. Bot. Voy. Sulph. 10. 1844. 

 Baja California; type from Magdalena Bay. 



Leaflets 8 to 20 mm. long ; petals 5 mm. long ; fruit 4 to 5 mm. long. 



8. Fagonia insularis Standi. Proe. Biol. Soc. Washington 24: 247. 1911. 

 Known only from Carmen Island, Baja California. 



Leaflets 1 to 9 mm. long ; petals 5 mm. long ; fruit 3 to 4 mm. long. 



9. Fagonia rosei Standi. Proc. Biol. Soc. Washington 24: 247. 1911. 

 Known only from the type locality, Tiburon Island, Baja California. 

 Leaflets 2 to 3 mm. long ; petals purplish, 7 mm. long. 



2. COVILLEA ' A^ail, Bull. Torrey Club 22 : 229. 1895. 



1. Covillea tridentata (DC.) Vail, Bull. Torrey Club 26: 302. 1899. 



Zygophylhtm tridentatum DC. Prodr. 1: 706. 1824. 



Larrea mexicana Moric. PI. Nouv. Amer. 71. 1839. 



Larrea glutinosa Engelm. in Wisliz. Mem. North. ]Mex. 93. 1848. 



Larrea tridentata Coville, Contr. U. S. Nat. Herb. 4: 75. 1893. 



Baja California and Sonora to Taraaulipas, Queretaro, and Durango. West- 

 ern Texas to Utah and southern California. 



Strong-scented shrub, 1 to 3.5 meters high ; leaves opposite, persistent, com- 

 posed of 2 oblong to obovate leaflets, these oblique, united at base, 5 to 10 mm. 

 long ; flowers solitary, the petals yellow, 8 to 10 mm. long ; fruit of 5 carpels, 

 densely pilose with long hairs. Mostly generally known as " goliornadora ; " 

 " hediondilla " (Sonora, New Mexico) ; "falsa alcaparra " (Sonora, San Luis 

 Potosi, Ramirez); " guamis " or " huamis " (San Luis Potosf, Chihuahua); 

 " hediondo " ( California ) . 



The creosote bush is one of the most characteristic shrubs of the dry plains 

 of northern Mexico, often covering wide areas to the exclusion of most other 

 woody plants. The flower buds, pickled in vinegar, are said to be eaten like 

 capers. The plant is much used in domestic medicine, especially for rheu- 

 matism, a decoction of the leaves being employed for baths or fomentations. 

 The decoction is said, also, to have remarkable antiseptic properties, and is 

 applied to bruises and sores. It is taken internally for gastric disturbances 

 and for venereal diseases. A reddish brown lac is often deposited upon the 

 branches by a small scale insect. This lac is used in some parts of Mexico for 

 dyeing leather red, and the Coahuilla Indians of California employ it as cement. 

 The same Indians use a decoction of the plant for intestinal complaints and for 

 tuberculosis. The Pima Indians of Arizona drink a decoction of the leaves as 

 as emetic, and apply the boiled leaves as poultices to wounds and sores. 



* George Barclay was a gardener at Kew, who accompanied H. M. S. Sulphur 

 for the purpose of making botanical collections. 



^ Named for Frederick Vernon Coville (18G7-), Curator of the U. S. National 

 Herbarium. Mr. Coville was botanist of the U. S. Death Valley Expedition of 

 1891, and published a volume dealing with the botanical features of that region 

 (Contr. U. S. Nat. Herb. 4), and he has published many other papers upon a 

 wide range of botanical subjects. He made a collection of plants in Sonora 

 in 1903. 



