622 CONTRIBUTIOISrS FROM THE NATIONAL HERBARIUM. 



7. Ditaxis sericophylla (A. Gray) Heller, Cat. N. Amer. PI. 5. 1900. 

 Argitliamnia sericophylla A. Gray in S. Wats. Bot. Calif. 2: 70. 1880. 



Baja California and Sonora. Southern Arizona and California ; type from 

 Arizona. 



Low shrub, sparsely leafy ; leaves 1 to 3.5 cm. long, entire, short-petiolate or 

 sessile, sericeous. 



8. Ditaxis manzanilloana (Rose) Pax & Hoffm. in Engl. Pflanzenreich IV 



147^': 59. 1912. 

 Argitliamnia vianzanilloana Rose, Contr. U .S. Nat. Herb. 1: 357. 1895. 

 Known only from the type locality, Manzanillo, Colima. 

 Slender shrub ; leaves ovate, 4 to 5 cm. long, acuminate, short-petiolate, 

 green, thinly sericeous, entire or denticulate. 



9. Ditaxis tinctoria (Millsp.) Pax & Hoffm. in Engl. Pflanzenreich IV, 



147^': 59. 1918. 

 Argithamnia tinctoria Millsp. Field Mus. Bot. 1: 302. pi. I'l. 1896. 

 Type from Xcholac, YucatSn. Nicaragua. 



Shrub, 1.3 meters high ; leaves ovate-lanceolate, 4 to 6 cm. long, acuminate, 

 nearly entire, short-petiolate, densely pilose beneath. "Azafran." 

 The plant is employed as a dye. 



10. CHIROPETALUM Juss. Ann. Sei. Nat. I. 25: 21. 1S32. 



1. Chiropetalum schiedeanum (Muell. Arg.) Pax in Engl. & Prantl, Pflanzen- 

 fam. 3': 45. 1890. 



Argyrothamnia schiedeana Muell. Arg. Llnnaea 34: 150. 1865. 



Nuevo Leon to Veracruz and Hidalgo ; type from Cerro Colorado. 



Slender shrub, 1 meter high or less, or more often, perhaps, herbaceous ; leaves 

 alternate, slender-petiolate, narrowly or broadly ovate, 1.5 to 6 cm. long, acute 

 or acuminate, serrulate, stellate-pubescent, at least when young ; flowers monoe- 

 cious, in slender axillary racemes ; capsule deeply 3-lobate. 



11. RICINUS L. Sp. PI. 1007. 1753. 



1. Ricinus communis L. Sp. PI. 1007. 1753. 



Common in cultivation in Mexico, and naturalized in some localities. Native 

 probably of tropical Africa, but now widely dispersed in tropical regions. 



Essentially an annual plant, but often shrublike, and sometimes becoming 

 ti'eelike and 9 meters high or even lai'ger, glabrous, glaucous ; leaves alternate, 

 large, palmately lobate, the lobes acuminate, dentate ; flowers monoecious, 

 apetalous, large, racemose ; fruit a large, smooth or echinate capsule. Com- 

 monly known as " higuerilla " ; " palma christi " (Oaxaca) ; " yaga-bilape," 

 " yaga-higo " (Oaxaca, Zapotec, Reko) ; " yutnu-nduchidzaha " (Oaxaca, Mix- 

 tec, Reko) ; " degha " (Otomi) ; " koch " (Maya); " tlapatl," " higuera infer- 

 nal" (Nueva Farmacopea Mexicana). 



The castor-bean is cultivated to some extent in Mexico for its seeds, which 

 are an important source of oil. This ( " aceite de castor " ) is well known 

 and much used in medicine because of its purgative properties. It is widely 

 employed as a lubricant, and has been used for illuminating purposes, in the 

 manufacture of soap, for the manufacture of the Turkey-red oil required in 

 the dyeing and printing of cotton goods, and for dressing tanned hides. In 

 India and China silkworms are fed on the leaves, and the stems have been 

 used for making paper. The ground seeds from which the oil has been ex- 

 tracted afford a valuable fertilizer. 



