A- ■/ 



72 CONTRIBUTIONS FROM THE NATIONAL n>:RBARIUM. 



and glabrous thronghout; leaflets all lanceolatej sessile, sliglilly aonminato, the 

 odd one 3 to 4J^ cm. long, the laterals notably siumIUt, ;ill obseuroly aubscrrate 

 or dentate: samaras large ior tlio foliage, abnost invarial)ly trir^uetrous, the fat-e 

 broadly round-t'ordate, the apex being narrower, yet ratlier broad an<l emarginate; 

 body round-oval, nut trausverse-rugose but deeply pittecbretieulute, a conspicunus 

 gland in each i>it, tlie Avhole body slightly circunivallafe, of Icr^y than the width of 

 the wing, the fruit as a whole 1.5 cm. long and tpiite as broad near the ba^e. 



Grand Canyon of the Colorado, Arizona, excellent specimen in tlie National 

 Herbarium, collected by J. W. Toumeyj July 11, IS\)2, 



47. Ptelea lutescens, sp. nov. 



Bark of all twigs and 1 tranches whitish and shining as well as strongly rugulose 

 and faintly and sparingly glandular-tuben-ulate: foliage light green, a little i")ale 

 beneath, of barely subcoriaceous texture, densely and minutely dotted on both fa(^es; 

 odd leaflet lanceolate above a rather longcuneate base, 4 to fi cm. long, laterals from 

 nearly as large to smaller by one-half, obliquely lanceolate, all lightly subserrate- 

 toothed and quite sessile: samaras large, suborbicular, 2 cm. wide and not <inite as 

 long, subtruncate across the broad summit, the base often slightly retuse; body oval, 

 of little jnore than half the width of the wing, faintly transverse-rugose and circuin- 

 valjate, not strongly gland-dotted; style and stipe about equal. 



Species of northwestern Arizona, iidiabiting canyons ti-ibutary to the (Inind Can- 

 yon of the Colorado, the best specimen from Red Cauyoi\ Trail, collected June 10, 

 1901, by Lester F, AVard (type in the National Herbarium). Younger material, with 

 fruit not mature, from Bright Angel Trail, liy Dr. C. Hart Merriam, May 10, 1903. 

 These last imperfect specimens have smaller relatively !)roader leaflets, and may 

 possibly represent another species. 



48. Ptelea elegansj sp. nov. 



Twigs much smoother than in the last, and straw-colored rather than whitish, 

 the rugosity less prominent: leaves thinner, twice as large, the middle hniflet lance- 

 olate, acuminate, all these sessile, obscurely subserrate-toothed: samara? fully 2 cm, 

 wide and of the same. length except as notched 1)roadly and deeply at both ends 

 between rounded cordate lobes; bo<ly obovoid, distinetly yet delicately transverse- 

 rugose not circumvallate, small dotted; style short, stipe none. 



Grand Canyon of the Colorado, Arizona, June 14, 18SH, D. T. ]McDougaI, the 

 shrub said to grow **in rich soil and in water." The only specimens seen are in 

 the National Herbarium. 



49. Ptelea confinis, sp, nov. 



Immature twigs of the season, short, crooked, whitish, rugnlose and polished, but 

 also sparingly pubescent; those a year or two old dull brownish, glabrate, less rugn- 

 lose, notably glandular-tuberculate: leaves small, of a light somewhat yellowisli 

 green above, paler and glaucescent beneath; odd leaflet 3 to 4 cm. long, rhombic- 

 lanceolate or merely ovate-lanceolate, the laterals almost as large, oblitjuely lanceo- 

 late, all acutish, sessile, finely and e^ fuly or very ubscurt'ly si-rrulate: samaras large 

 for the foliage, suborbicular, 1.5 cm. long and of the same brradth, retuse at base, 

 minutely cuspi<late-acute at apex; body oval, of less than the width of the wing, con- 

 spicuously transverse-rugose and d<ttted; style and stipe both short. 



El Papo, Texas, April, 1881, G. K. Vasey; specimens with fruit unripe, but appar- 

 ently almost or quite full grown. 



The plant is interesting as l)elonging to that group of white-barked species inhab- 

 iting the region of tlie Crund Canyon of tjie Colorado in northwestern Arizona and 



adjacent Utah. 



The material examined is on four sheets in the National Herbarium, among which 



I would name that on sheet 15254 as the type. 



