436 SAPIXDACE.E. Acer. 



■i— Fruit glabrous : species of the Eastern States and Mississippi Valley. 



A. Pennsylvanicum, L. (Stru'ed Maple, Moosewoou.) Shrub or small tree with 

 siiiooihish longitudinally striped bark : leaves large, thin, dark green, glabrous above, 

 scarcely paler and tawny pulverulent-puberulent beneath, finely, sharply and somewhat 

 doubly serrate all around, rounded or soniewliat cordate at the base ; lobes 3 to 5 sharply or 

 caudately acuminate ; flowers large, rather few in the simple flexuous racemes ; peilicels 

 slender, scarcely spreading: petals pale green, obovate, slightly exceeding tiie oblong acut- 

 ish sepals : filaments inserted outside the crenate disk : no rudimentary j)istil in the cf flow- 

 ers: fruit at nuiturity 1^ to 2 inches in breadth; the outer edges of tiie wings making a 

 very obtuse angle. — Spec. ii. 1055 (as Pensi/lvunicum) ; Michx. Fl. ii. 252; Torr. «Sb Gray, 

 Fl. i. 246; Gray, Gen. 111. ii. 200, t. 174, f. 1-4; Emerson, 1. c. 566, with plate; Sargent, 

 Silv. ii. 85, t. 84, 85. A. Canadense, Marsh. Arb. 3. A. striatum, Du Roi, Diss. 58 ; Michx. f. 

 Hist. Arb. Am. ii. 242, t. 17. — Shaded situations protected by other trees. Nova Scotia, 

 New Brunswick, and Lower Canada to Minnesota and south to the mountains of Georgia; 

 fl. May, June ; fr. July, August. Several nearly related species in E. Asia. 

 ■i— -f— Body of fruit soft- or more or less arachnoid-tomeutose at length glabrate : geron- 



togeous species freciuently planted. 

 A. Pseudo-plAtaxus, L. Spec. ii. 1054, the Sycamore Maple, with thickish 5-lobed 



bluntly serrate leaves dark green above and much paler beneath, is connnon in cultivation, and 



self-sown seedlings are sometimes found in parks, on lawns, &c., of cities. (Cult, from the 



Old World.) 



-1— -1— -t^ Body of the fruit hirsute : species of the We.st. 



A. macroph^Uum, Pursh. A tall tree with thick rough and furrowed bark : younger 

 l)arts witii a milky juice : leaves large, of firm texture, deeply (3-)5-parted, at first soft- 

 pubescent, later quite glabrate above and with only a microscopic pubcrnlence beneath, 

 reticulate-veiny ; the lobes with 1 to 5 coarse irregular teeth, the margins otiierwise entire: 

 racemes rather many-flowered : anthers sagittate ; filaments pubescent at the base, inserted 

 above (witliin) the disk: fruit very large, wings (each 1 to 2 inches long) diverging mostly 

 at an acute rarely obtuse angle ; the body of the carpels large, upwardly bristly witli stiff 

 tawny hairs.— Fl. i. 267 ; Nutt. Sylv. ii. 77, t. 67 (by error numbered 68) ; Hook. Fl. Bor- 

 Am. i. 112, t. 38 ; Torr. & Gray, Fl. i. 246; Torr. Pacif. K. Rep. iv. 74, & Bot. Mex. Bound. 

 47 ; Brew. & Wats. Bot. Calif, i. 107 ; Sargent, Silv. ii. 89, t. 86. 87. A. palmatum, Raf. 

 New Fl. Am. i. 48, not Thunb. — Preferring rich soil near streams, in the Sierra Nevada and 

 on the Pacific Coast from Alaska to S. California; fl. April, May ; fr. June to September. 

 Specimens with 3-5-earpelled fruits have been found in Washington by Suksdorf. 



§ 2. Glabra, Pax. Flowers polygamous, with both calyx and corolla : in- 

 florescence umbelliform or corymbose ; pedicels slender : disk well developed. — 

 Pax in Engl. Jahrb. vi. 327. 



* Petals flat, about equalling the sepals : leaves 3-5-lobed or palmately S-foliolate. 



A. glabrum, Torr. Shrub or small low-branching tree with smoothish bark : branchlets 

 glabrous, liglit brown : leaves mo.stly rather small, glabrous except for a sparse tawny pul- 

 verulence more or less persistent especially upon the veins beneath, 3(-5)-lobed or often 

 upon the same trees or branches 3-foliolate ; lobes or leaflets unequally and somewhat in- 

 cisely serrate, acute or obtusish : inner bud-scales lance-oblong, soft-pubescent on the upper 

 surface, roseate, usually tipped with a rudimentary lamina : inflorescences few-flowered, in 

 anthesis short, spreading or nodding : petals rather narrow, spatulate-oblong, veiny, about 

 equalling the oblong sepals : stamens about 8, shorter than or barely equalling the floral 

 envelo{)es ; filaments borne in sockets of the disk : rudiment of pistil in d flowers none : 

 fruit strongly and irregularly rugose ; wings diverging at an acute or right angle. — Ann. 

 Lye. N. Y. ii'. 172 ; Torr. & Gray, Fl. i. 247, 684 ; Nutt. Sylv. ii. 86 ; Wats. Bot. King Exp. 

 52; Brew. & Wats. Bot. Calif, i. 107 ; Sargent, Silv. ii. 95, t. 89. A. Donglnsii, Hook. Loud. 

 Jour. Bot vi. 77, t. 6. Var. TRiPARxfruM, Pax (in Engl. Jahrb. vii. 218 ; A. tripartittim, 

 Nutt. in Torr. & Gray, Fl. i. 247, & Sylv. ii. 85, t. 71), is a form having leaves mostly 

 although inconstantly 3-foliolate. — Rocky ground, in woods and along streams, mountains 

 of Colorado, New Mexico, and Arizona, to S. Central California, Brit. Columbia, and 



