70 CONTRIBUTIONS FROM THE NATIONAL HERBARIUM. 



8. ARTHROSTYLIDIUM Rupr. M6m. Acad. St. Pgtersb, VI. Sci. Nat. 3': 117. 



1839. 

 1. Arthrostylidium racemiflorum Steud. Syn. PI. Glum. 1: 336. 18-54. 



Veracruz; the type from Mexico, but the definite locality unknown. Costa 

 Rica. 



Several other species of bamboos have been described from Mexico, but their 

 validity and identity are uncertain. 



8. PHOENICACEAE. Palm Family. 



Refebence: Oersted, Nat. For.Kjobenhavn Vid. Medd. 1858: 1-54. 1859. 



The palms are one of the most interesting and important groups of Mexican 

 plants. Although the number of species represented is not nearly as large as in 

 Central America, or farther southward in South America, those which are 

 found in Mexico are of great economic importance. The plants attract 

 attention because of their curious and beautiful forms, and they are favorite 

 ornamental plants in Mexican parks and gardens. Besides the native species, 

 some exotic ones are cultivated. The species are widely distributed in Mexico 

 and often form extensive forests. 



The trunks are used for making the walls and roofs of houses, and the leaves 

 are the usual material employed for thatch. The juice of the stems usually 

 contains sugar, and may be fermented to obtain intoxicating drinks. The 

 tough leaves are made into hats, mats, raincoats, and other articles, and their 

 fiber furnishes cordage. The fruits of many of the species are edible, and the 

 seeds contain large quantities of oil. 



The writer is under special obligations to Mr. O. F. Cook for assistance in the 

 preparation of the account of this family. 



Leaves flabellate. 



Calyx and corolla united and forming a 6-dentate cup ; ovary of a single 



1-ovulate carpel. Petioles unarmed 1. THRINAX. 



Calyx and corolla distinct ; ovary of 3 distinct or more or less united carpels. 



Style or stigma basilar in fruit. Petioles unarmed 2. INODES. 



Style or stigma terminal in fruit. 



Trunk armed with long spines— 4. ACANTHORRIZA. 



Trunk unarmed. 



Petioles smooth. Fruit globose, about 12 mm. in diameter. 



5. CRYOSOPHILA. 

 Petioles with dentate or denticulate margins. 

 Branches of the inflorescence, at least the primary ones, subtended 

 by spathes. 



Leaf sheaths split at base 3. WASHINGTONLA.. 



Leaf sheaths not split at base 6. ERYTHEA. 



Branches of the inflorescence not subtended by spathes. 



7. BRAHEA. 

 Leaves pinnate or pinnatifid, or sometimes simple and bifid at the apex. 



Ovary of 3 distinct carpels, only one normally developed 8. PHOENIX. 



Ovary of united carpels. 



Fruit baccate, without a bony endocarp. 



Flowers sunk in the fleshy rachis of the Inflorescence. 



Style lateral, beside the one fertile cell of the ovary 9. QEONOMA 



Style rising from between the 3 fertile cells of the ovary. 



10. CALYPTROGYNE. 



