64 CONTRIBUTIONS FROM THE NATIONAL HERBARIUM. 



21. Ptelea parvula, sp. nov. 



Apparently a low gnarled shrub, the older branches short, stout, knotted, aah- 

 gray, glabrate, the very short twigs of the season reddish and tomentulose: leaves 

 Babooriaoeous, small, dull pale-green above and with -"me pubescence along the 

 veins, whitish 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 Bmaller, all 

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



mere trifle less, the whole very thick ami linn; body oval, not pr inently elevated 



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

 rug< «e, tin- dots i ibecure. 



Summit of the Sierra Blanca, southern New Mexico, August 1. ls«i7, E.O. Wooton, 

 his number 658 as in my set of his plants; but with 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, s|». nov. 



Shrub •"'> meters high, all twigs and younger branches glabrous, nearly Bmooth, 

 chestnut-color: leaves numerous, small, quite linn hut hardly subcoriaceous, very 

 glaucous on both faces, very sparingly pubescent beneath, leaflets 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 wing, strongly and usually transversely rugose, lightly 

 circum vallate; style and stipe equal, both very short. 



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

 western Chihuahua in 1885, by Dr. I-]. Palmer; his distribution number L52 as in the 

 National I lerhariuni. 



23. Ptelea monticola, Bp. nov. 



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

 leaves subcoriaceous, light green and Btrongly punctate above, beneath glaucescent 

 and slightly villous as well as plainly punctate; odd leaflet broadly cuneate-obovare, 



:!.."> to ;> cm. long, obtuse or refuse, the pair not much smaller, very obliquely ovate, 

 all lightly crenate, hut the crenatures at length becoming obscure by revolution of 

 the whole margin: samaras not large, round-ohovate, 1.5 cm. Ion-, of about the 

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

 ginate or scarcely more than truncate ; body large, thick, broader than the widest 

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

 dotted. 



Summit of the Guadalupe Mountains, western Texas, August, 1881, \h-. Y. Havard; 

 a single but full sheet of specimen- in the National I lerhariuni. The species is prob- 

 ably local, for the < ruadalupe Mountains are completely isolate* 1. yet our shrub hears 

 marks of affinity for /'. polyadt nia, the habitat of which is the hanks of the ( lanadian 

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

 samaras differ hoth 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 ami white-dotted: mature leaves firm, hardly subcoriaceous, bright green and 

 almost glabrous above, as nearly glabrous beneath hut pale and glaucescent ; odd leaf- 

 let 4 to LOcm. Ion-, usually ovate-rhomboid or almost rhombic, acute at hoth ends, 

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

 obliquely rhomboid-oval, being notably inequilateral, all distinctly and doubly ser- 

 rate-toothed: samara- round-obovate, 1.6 to 1.8 cm. Long, usually abruptly narrowed 

 at base and cuspidately acute at apex, oral least mucronate by the short style; hody 



