624 TREES OF NORTH AMERICA 



minutely apiculate, attached below the middle, grooved on the back; ovary raised 

 upon and confluent with a fleshy slightly 10-augled gynophore, papillose-glandular 

 on the surface, 5-celled, the cells opposite the petals, terminating in a fleshy elon- 

 gated style; stigma slightly 5-lobed; ovules 6 in each cell, inserted in 2 ranks on its 

 inner angle, subhorizontal; micropyle inferior. Fruit a woody terete oblong capsule 

 tapering at the ends, crowned with a subulate persistent style, septicidally 5-valved, 

 the valves 2-lobed at the apex; outer coat thin, fleshy; inner coat woody. Seed soli- 

 tary or in pairs, ascending, subovate, flattened; seed-coat subcoriaceous, papillate, 

 produced below into a subfalcate membranaceous wing; embryo surrounded by thin 

 fleshy albumen, erect; cotyledons oval, compressed; radicle very short, inferior. 



The genus is represented by a single species. 



The generic name is that by which this plant was known to the Mexicans of Arizona 

 at the time of its discovery. 



1. Canotia holacantha, Torr. 



Leaves 0. Flowers \'-\' in diameter, appearing from June until October. 

 Capsule 1' long; seed about f long. 



A small shrub-like tree, sometimes 20-30 high, with a short stout trunk rarely a 

 foot in diameter; or often a low spreading shrub. 



Distribution. Dry gravelly mesas on the Arizona foothills, from the White 





Mountain region to the valley of Bill Williams's Fork in the northwestern part of 

 the territory, and on Providence Mountain in southern California. 



XXXIII. ACERACEJEJ. 



Trees or rarely shrubs, with limpid juice, terete branches, scaly buds, their 

 inner scales accrescent and marking the base of the branclilets with ring-like 

 scars, and fibrous roots. Leaves opposite, long-petioled, simple, palrnately 

 3-7-lobed or pinnately 3-5-foliolulate, usually without stipules, deciduous, in 

 falling leaving small U-shaped narrow scars showing the ends of 3 equidistant 

 fibro-vascular bundles. Flowers regular, diceciously or monoeciously polyga- 

 mous, rarely perfect or dioacious, in fascicles produced from separate lateral buds 

 appearing before the leaves or in terminal and lateral racemes or panicles 



