^^_ 



64 CONTRIIUTTIOXS FROM THE JNTATIO^^AL IIKRIiARlUM. 



21. Ptelea parvula, np. nov. 



Apparently a low ^narlod slirub, the older branches short, stout, knotted, ash- 

 graVj glahrate, the very short twigs of the season re<ldiwh and tomentulose: leaves 

 flubcoriaceous, pmall, dull palo-green above and with pome pubescence along the 

 veinSj wliitish beneath with bloom and also a thin white tomentulose pubescence; 

 odd leaflet ovate or obovate, only 2 to 5 cm. long, the pair not much smaller, all 

 acute, subentire: samara very small, suborbicular, about 1 cm, long, the width a 

 mere trifle less, the wliole very thick and firm; body oval, not prominently elevated 

 above the surface of the wing, and Hke it coarsely reticulate rather than definitely 

 rugose, the dots obscure. 



Sununit of the Sierra Blanca, soutliern Xew Mexico, August 1, 1897, E. 0. Wooton, 

 his number 058 as in my set of his plants; but witii no note of size or special location 

 other than that of the altitude of 6,300 feet, which is about that of the summit. 



22. Ptelea glauca, sp. nov. 



Shrub 3 njcters high, all twig^ and younger branches glabrous, nearly smooth, 

 chestnut-color: leaves numerous, small, quite firm but hardly subcoriaceous, very 

 glaucous on both faces, very sparingly pubescent beneath, leallrts almost equal, all 

 conspicuously petiolate, about 4 cm. long, lanceolate, obtuse or acute, crenulate: 

 samaras orbicular, the largest 1.5 cm. broad and long, emarginate; body round-oval, 

 broader than the width of the whig, strongly and usually transversely rugose, lightly 

 circumvallate; style and stipe equal, botli very short. 



Elegant and very peculiar species known only as obtained somewhere in south- 

 western Chihuahua in 1885, by Dr. K. Pahner; his distribution number 152 as in tlie 

 National Herbarium. 



23. Ptelea monticola, sp. nov. 



Twigs of the season dull-brown, velvety-puberulent, tlie older glabrate and darker: 

 leaves subcoriacouus, light green and strongly punctate above, beneath glaucescent 

 and slightly villous as well as plainly punctate; odd leaflet broadly cuneate-obo\ ate, 

 3.5 to 5 cm. long, obtuse or rctuse, the pair not much smaller, very obliquely ovate, 

 all lightly crenate, but the crenatures at length becoming obscure by revoluti<in of 

 the whole margin: samaras not large, niund-t»bovate, 1.5 cm. long, of about the 

 same breadth above the middle, the base abruptly acutish, the apex slightly emar- 

 ginate or scarcely more than truncate ; bo<ly large, thick, broader than the widest 

 part of the wing, round-obovate, strongly rugose, lightly circumvallate, obscurely 

 dotted. 



Summit of the Guadalupe Mouiitains, western Texas, August, ISSl, Dr. V. Havard; 

 a single but full sheet of specimens in the National Plerbarium. The species is prob- 

 ably local, for theCJuadalupe Mountains are completely isolated, yet our shrub bears 

 marks of affinity for r. pohjadenia^ the habitat of which is the banks of the Canadian 

 River, 300 miles to the northward. Its foliage, however, is very different, and the 

 samaras differ both in outline and markings. 



24* Ptelea betulifolia, sp. nov. 



Twigs of the season chestnut-color, roughened with short narrow gland-tipped 

 ridges, glabrous and almost shining, even those of the second season as bright in 

 color and white-dotted: mature leaves firm, hardly subcoriaceous, bright green and 

 almost glabrous above, as nearly glabrous beneath but pale and glauceacent; odd l(^af- 

 let 4 to 10 cm. long, usually ovate-rhomboid or almost rhombic, acute at both ends, 

 but at base tapering to a short but definite petiolule, the pair smaller by one-tliird, 

 o1)!iquely rhomboid-oval, being notably inequilateral, all distinctly and doubly ser- 

 rate-toothed: samaras round-obovate, hO to 1.8 cm. long, usually abruptly narrowed 

 at base and cuspidatel}' acute at apex, or at least mucronate by theshort style; botly 



