202 ACERACE^. 



destitute of albumen. E>rBRyo conduplicate ; the oblong 

 and flat foliaceous cotyledons applied face to face, bent 

 down near the middle, and obliquely incumbent upon the 

 descending slender radicle. 



Trees, with a light green bark on the young shoots, and 

 scaly buds. Leaves opposite, exstipulate, petioled, pinnate- 

 ly tri - quinquefoliolate ; the leaflets induplicate in verna- 

 tion, ovate or oblong, petiolulate, pinnately veined, incisely 

 toothed or lobed, membranaceous. Flowers small, greenish, 

 pendulous, appearing with or a little before the leaves, from 

 separate (and in the sterile plant usually aggregated) lateral 

 buds ; the staminate cymose-fascicled, on long and capillary 

 pedicels ; the pistillate racemose (the rachis more prolonged), 

 on shorter (opposite) pedicels: the lowest bracts membrana- 

 ceous, the upper minute, deciduous. 



Etymology. The name, so far as I know, first appears in the phrase, 

 " Arbor exot., foliis fraxini instar pinnatis et serratis, Negundo perperam 

 credita," of Ray's Hist. Plant. I do not find that it is used as a popular 

 name of the tree in any part of the United States. 



Geographical Distribution, Properties, &c. These are mentioned 

 under the order. 



PLATE 175. Negundo aceroides, AfoncA. ; — a staminate branchlet, in 

 flower. 



1. Raceme of a pistillate plant, in flower; of the natural size. 



2. A staminate flower, magnified. 



3. A stamen, more magnified. 



4. A pistillate flower, magnified. 



5. A transverse section of its ovary, showing the collateral ovules. 



6. Magnified ovary, with the cells cut open, showing the ovules. 



7. An ovule, more magnified. 



8. The fruit, with one carpel cut open to show the seed ; natural size. 



9. A magnified seed, divided vertically, showing the embryo. 

 10. The embryo of the same, partly spread out. 



