GREENE PTELEA IX I'HK WEST AND 90UTHWE8T. il 



-j. 'nii~: nevertheless the whitish and Bhining twigs attest it- being really of the 

 present singular group of northern Arizona, though differing considerably from most 

 others as to its broad obovate leaflets of rather thinnish texture. 



43. Ptelea nitida, sp. nov. 



Shrub perhaps low, the branching at least compact, the fructification copious, in 

 short and very few-flowered panicles; all twigs and branches whitish, very smooth 

 and somewhat shining: leaves small, of the -a me lighl green on both faces, glabrous, 

 strongly punctate; middle leaflet ovate-lanceolate, ;! to 4 em. long, acutish at each 

 end, obscurely crenulate, the laterals oval to lanceolate and from nearly or quite 

 as large to smaller by about one-third, all sessile: samaras large for the leaves, 

 all triquetrous, the faces round-obcordate, 1.5 cm. in length and breadth, retuse at 

 base but obcordate al the broad summit; body oval, of less than the width of the 

 wing, very faintly circnmvallate, lint also the rugosity equally 1<>\\ and obscure, as 

 is also the reticulation of the wing, the fruit as a whole remarkably smootb and pol- 

 ished, the scattered punctuation hardly more obvious. 



Species known to me only as in the Herbarium of the California Academy from 

 somewhere in the Grand Canyon of the Colorado in Arizona, collected by E. 0. 

 Wooton, July 8, 1892. 



44. Ptelea argentea, sp. nov. 



Twigs whitish and polished, much smoother than in any others of the group, 

 neither ridges nor glands obvious to the unaided eye: leaves hard and quite coria- 

 ceous, of a bright but not shining green above, very pale and with a silvery gloss 

 beneath, yet every where perfectly glabrous; odd leaflet lanceolate or evenslightly 

 rhomhic-lanceolate, acute, :'> to 4."> cm. long, laterals smaller by about one-fourth, 

 lanceolate, all sessile, obscurely subserrulate: samaras large tor the foliage, usually 

 triquetrous, those 2-winged and plane-suborbicular bul broader than lon:_ r . the breadth 

 1.5 cm.; body in all elongated-obovate, marked throughout its length with obscure 

 low hut quite transverse ridges and with low circumvallation, the dots many, yel 

 inconspicuous; style slender, not long, yet longer than the short cuneiform stipe. 



This species, remarkable for its leathery foliage, silvery-lustrous beneath, is known 

 to me only as collected by Dr. F. II. Knowlton, somewhere in the < .rand Canyon of 

 the Colorado, September 10, 1889, the specimens filling two sheets m the National 

 Herbarium (one the type). Notwithstanding the luster on the lower face ol the 

 leaflets, I am unable t<> detect any indument there, either lepidote or others ise. 



45. Ptelea neglecta, sp. nov. 



Mature twigs <>t the season light chestnut-color, short-rugulose, glandular-tuber- 

 culate, glabrous, those a year old whitish, smoother and Bhining. leaves equally 

 light-green on both faces, subcoriaceous, glabrous, conspicuously ami darkly gland- 

 dotted, <>dd leaflet lanceolate, .!."> to 5 cm. long, obtuse, tin- pair commonly little 

 smaller, egual-sided, alt obscurely or not at ail crenate sessile samara very large 

 lor the loliage, 2 to 2.2 cm. long, broadly oval or obovate, retuse at i>oth ends, bod) 

 rat her narrowly oval and long, oi the width ol the wing, not rugose hi it \ er\ strong j 

 gland-dotted the dots, however, in some disposed in rather definitely transverse 

 lines. Btyle and stipe subequai, both short. 



Near Kanab, southern Utah, A. Wetherill, 1897; the only specimens in the Herb- 

 arium of the California Academy, consisting ol two sorry fragments, but well in 

 fruit, and evincing a marked species. 



46. Ptelea triptera, sp. nov. 



Shruh apparently low, the whitish or straw-colored branches more glandular- 

 leaves small, in maturity subcoriaceous, yellow-green 



