STANDLEY TKEES AND SHRUBS OF MEXICO. 1133 



Coi-oUa lobes or petals imbricate or none. 



Flowers in terminal panicles. Corolla of 4 distinct petals. 



4. HESPERELAEA. 

 Flowers axillary or lateral. 



Corolla none or of 1 or 2 petals ; calyx none or minute. 



5. FGRESTIERA. 

 Corolla gamopetalous ; calyx well developed 6. OSMANTHUS. 



1. FRAXINUS L. Sp. Tl. 1057. 1753. 



References : Wenzig, Die Gattung Fraxinus, Bot. Jahrb. Engler 4: 165-188. 

 1883; Lingelsheim, Vorarbeiton .^u eincr Monographic der Gattimg Frcurmus, 

 Bot. Jahrb. Engler 40: 185-223. 1907; Rehder, The genus Fraxinus in New 

 Mexico and Arizona, Proc Auier. Acad. 53: 199-212. 1917; Lingelsheim in 

 Engl. Pflanzenreich IV. 243': 9-61. 1920. 



Shrubs or trees ; leaves opposite, usually odd-pinnate, rarely simple ; flowers 

 green or white, dioecious or polygamous, fasciculate or paniculate; calyx 4- 

 lobate or dentate, or none ; petals 2 to 4, or commonly absent ; stamens usu- 

 ally 2; fruit a samara, winged at the apex, usually 1-seeded. 



The various species of ash are common in temperate regions of the Northern 

 Hemisphere. Some of them furnish strong wood which is useful for building 

 purposes, interior finish, furniture, and tool handles. They make excellent 

 shade trees and are often planted on that account. The bark contains a glu- 

 coside, fraxin, and, like the leaves, has been used in Mexico, the United 

 States, and Europe as a tonic and febrifuge. A decoction of the leaves has 

 been employed in Mexico particularly for yellow fever and malaria. The 

 leaves are said also to have purgative properties, and they have been used for 

 gout and rheumatism. FraxinuH ornus L., a species of the INIediterranean 

 region, produces from cuts in the bark an exudate, which is an official drug, 

 manna, of the United States Pharmacopoeia. It is used in medicine as a 

 gentle laxative. 



There is a popular belief in some parts of the southern United States that 

 ash leaves are so offensive to rattlesnakes that the latter are never found 

 on land where the trees grow. Hunters are said sometimes to stuff their 

 boots with ash leaves as a preventive of rattlesnake bites. 



The ordinary Spanish name for the ash tree, and the one generally em- 

 ployed in Mexico, is " fresno," a derivative of the Latin " fraxinus." The 

 following names are reported for species of doubtful identity : " Yaga-guillaa," 

 " yaga-nisse " (Oaxaca, Zapotec, Reko) ; " paramu " (Michoacan, Tarascan, 

 Ramirez) ; " demettza " (OtomI, Buelna). 



Petioles and leaf rachis narrowly winged ; leaves sometimes simple or tri- 

 foliolate. 

 Leaves all pinnate, with 5 or more leaflets. 



Leaflets coarsely serrate 1. F. purpusii. 



Leaflets entire or nearly so. 



Leaflets small, 1 to 3 cm. long, 2.5 to 8 mm. wide. 



Leaflets narrowly oblanceolate 2. F. greggii. 



Leaflets ovate 3. F. rufescens. 



Leaflets large, mostly 3.5 to 6 cm. long and 8 to 20 cm. wide. 



Leaflets glabrous above 4. F. Echiedeana. 



Leaflets pilose on both surfaces 5. F. attenuata. 



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