TREES AND SHRUBS OF MEXICO/ 



By Paul C. Standley. 



65. OXALIDACEAE. Wood-sorrel Family. 



One other genus, Bioplnituni, occurs in Mexico. 



1. OXALIS L. Sii. I'l. 433. 17.^3. 

 Low shrubs or sometimes lierbs, pubescent ; leaves alternate, pinnately 3-folio- 

 late; flowers small, perfect, usually cymose ; sepals 5, Inferior; petals 5 (yellow 

 in the species here listed), deciduous; stamens 10, the filaments united into a 

 tube below ; styles filiform or subulate ; fruit a small oblong or columnar cap- 

 sule, 5-celled. 



Numerous herbaceous species are found in Mexico. The name " socoyol " 

 (from the Nahuatl xocoyolli, " sorrel") is applied to some species. 



Longer filaments not appendaged 1. O. camporum. 



Longer filaments appendaged en tlie back. 

 Leaflets acute or acuminate. 



Leaflets linear or linear-oblong 2. O. angnstifolia. 



Leaflets ovate or lance-ovate 3. 0. sepium. 



Leaflets, at least most of them, emarginate at the apex. 



Capsule glabrous 4. 0. yucatanensis. 



Capsule pubescent on the angles 5. 0. neaei. 



1. Oxalis camporum T. S. Brandeg. Univ. Calif. Publ. Dot. 4: 377. 1913. 

 Veracruz ; type from Baiios del Carrizal. 



Leaflets 2.5 cm. long and 1 cm. wide or smaller, pubescent. 



2. Oxalis angustif olia H. B. K. Nov. Gen. & Sp. 5 : 249. 1822. 

 Lotoxalis anffustifolia Rose, Contr. U. S. Nat. Herb. 10: 115. 1906. 

 Known only from the type locality, near La Venta del Peregrine. 



Plants about 20 cm. high; leaflets 1.5 to 2.5 cm. Ifiig, glabrous; petals twice 

 as long as the sepals. 



3. Oxalis sepium St. Hil. Fl. Bras. Merid. 1 : 111. 1825. 

 Oxalis acuminata Schlecht. Linnaea 5: 224. 1830. 



Oxalis Unde7iii Turcz. Bull. Soc. Nat. MoScou 31': 429. 1858. 

 Lotoxalis sepium Small, N. Amer. Fl. 25: 48. 1907. 



Guerrero and Oaxaca to Veracruz. Central America. West Indies, and South 

 America ; type from Brazil. 



' The first installment of the Ti-ees and Shrubs of Mexico, comprising the 

 families Gleicheniaceae to Betulaceae, was published as Part 1 of Volume 23, 

 Contributions from the U. S. National Herbarium, pp. 1-170, October 11, 1920 ; 

 the second installment, comprising the families Fagaceae to Fabaceae, as Part 2, 

 pp. 171-515, July 14, 1922. 



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