160 



BETULA 



BIARUM 



Begel.), Lvs. broad-ovate, usually truncate at the 

 base. Var. p6ndula, Hort. Branches slender, dis- 

 tinctly pendulous ; cult, in several different forms, as 

 var. p^ndula laciniita, Hort., with laciniate lvs.; a 

 very graceful form (Pig. 234); var. p6ndula 61egans ; 

 var. p6ndula Yoiingi, and others. 



(2) pub6scens, Ehrh. (B. odor&ta, Bechst.). Less 

 pendulous or upright, sometimes shrubby ; branchlets 

 usually pubescent, not glandular : lvs. ovate, pubes- 

 cent beneath, at least when young : cones pendu- 

 lous or erect. The first grows more in dry situations, 

 while the latter is found growing in moist places, 

 often in swamps. To this subspecies belong the follow- 

 ing varieties : Var. ezc61sa, Begel. (S. excilsa, Ait.). 

 Tree : lvs. ovate, short petioled, pubescent beneath. 

 Var. pub6scens, Kegel. Branches and lvs. pubescent, 

 at least when young ; lvs. ovate, acute. Var. urtici£6- 

 lia, Spach. Lvs. small, deep green, Irregularly in- 

 cised-serrate, unequal at the base. Var. Carpitica, 

 Kegel, F6ntica, Dipp., and tortu6sa, Kegel, are small 

 trees, without any horticultural value. 



cc. Trunk with dark bronse-colored bark. 



11. occident&lis, Hook. Small tree, occasionally 40 ft. ; 

 branchlets slender, glandular : lvs. broadly ovate or 

 nearly orbicular, acute or obtuse, sharply serrate, short- 

 petioled, glabrous or sparsely pubescent at the veins be- 

 neath, 1-2 in. long : cones 1-lM in. long ; bracts with 

 erect, oval lobes, the middle one usually longer. North- 

 west Amer., east to Dakota and Nebraska. S.S. 9: 453. 



BB. Wings smaller than the nut: shrubs 1-15 ft.: lvs. 



small, short-petioled : cones erect. 



0. Branchlets glandular, not pubescent. 



12. glanduldsa, Michx. Only 1-4 ft. : lvs. short-peti- 

 oled, rounded or cuneate at the base, orbicular or 

 broadly obovate, obtuse, dentate, glabrous, ]4-l% in. 

 long : cones peduncled, ii-%m. long : lobes of bracts 

 nearly equal, slightly spreading. Newfoundland to 

 Alaska, south to Michigan, and in the Kocky Mountains 

 to Colorado. B.B.I: 510. 



oc. Branchlets pubescent or nearly glabrous, not 

 glandular. 



13. ptunila, Linn. Usually 2-8 ft., rarely 15 : branch- 

 lets tomentose or pubescent, at least when young : lvs. 

 orbicular or oval, acute or obtuse, coarsely dentate, pale 

 and glabrous or pubescent beneath, K-2 in. long: cones 

 peduncled, H-l in. long ; lateral lobes of the pubescent 

 bracts spreading, shorter than the middle one. New- 

 foundland to Minn., south to Ohio. B.B. 1:511. Var. 



fastigi&ta, Hort. {B. humilis 

 fastigiata, Hort.). Of distinct, 

 upright growth. B. pumila x 

 lenta is shown in G.F. 8:245. 



14. nkns,, Linn. Low, spreading, rarely 4 ft.: Iva. 

 o' bicular or cuneate-obovate, crenate, rounded at apex, 

 glabrous, M-Mln. long : cones nearly sessile, ii-%in. 

 long ; the upper bracts usually entire, the lower ones 





233. Leaves of Betula alba. Natural size. 



334. Cut-leaved ^Veepine Birch— Betula alba. 



3-lobed. Arctic N.E. Amer., N.Eu., Siberia. B.B. 1:511. 

 —A low, graceful shrub for rockeries and rocky slopes. 

 B. oiraoides, Hamilt. (B.cylindrostaohya.WaU.). Tree, 50-80 

 ft.: bark brown : lvs. ovate-oblong, doubly cuspidately serrate: 

 cones racemose. Himal. Tender.— B. ai^j^sfris, Pries — B. inter- 

 media.— B. carpinifblia, Elirh.= B. lenta.— -B. corylifdlia, Begel. 

 Allied to B. nigra, Lvs. broad elliptic or obovate, coarsely den- 

 tate : cones cylindrical. Japan. JB, cylindrostAehyaj 'W&U.= 

 B. alnoides.— B. DahArica, Pall. Tree, to 60 ft.: bark brown : 

 lvs. ovate, pubescent on the veins beneath, 1-2 in. long : cones 

 oblong. Dahur., Manchuria.— £. fruticdsa, Pall. Shrub, to 15 

 ft.: lvs. ovate, glabrous at length and usually glandular be- 

 neath, 1-2 in. long. Siber., Manchuria. — B. OmMini, Bunge= 

 B. fruticosa. — B. grdndis. Schrad.^B. papyrifera. — J5. grbssa, 

 Sieb. & Zuec. Allied to B. lenta. Lvs. ovate, unequally serrate, 

 /^-2 in. long: lobes of bracts rounded. Jap.— .B. hUmilis, 

 Sohrank. Two to 6 ft.: branchlets glandular : lvs. J^-lKin. 

 long, orenately serrate, glabrous. M. and N. Eu., N. Asia.— B. 

 hpbrida, Bechst. Natural hybrid of B. pendulaXpubesoens. 

 Tree.— B. intermedia, Thomas (B. albaXnana). Shrub: lvs. 

 orbicular or ovate, %-l in. long, glabrous. N. Eu.— B. Med- 

 widjewi, Eegel. Tree, allied to B. Ermani : lvs. elliptic, 8-11- 

 nerved : cones cylindrical. Trans-Caucasia. Gt. 36, p. 384.— 

 B. Baddedna, Trautv. Allied to B. fruticosa. Tree : lvs. small, 

 ovate, pubescent on the veins beneath : cones oblong. Cauca- 

 sus. Gt. 36, p. 384.— J3. ulmifblia, Sieb. & Zuoo. 

 Tree: lvs. ovate, doubly serrate, with 10-14 pairs 

 of veins : bracts of cone with linear oblong 

 lobes. Jap.— J?.roun£ri^^dwia, Hort.=B. alba, 

 var. pendula Youngi. Alfred Rehder. 



BIABITM (old and obscure name). 

 Aro\dece. Dwarf, tuberous perennials of 

 the same tribe with our native jack-in- 

 the-pulpit. They are hardy in England, 

 but probably are suitable only for pot-cul- 

 ture in the northern U. S. They have a 

 spathe which is tubular at the base, mostly 

 with a long limb, and usually a long tail- 

 like spadix. They grow a few inches high. 

 Odd. Little known in America. 



tenuifdlinm, Sohott {Arum tenuifdlium, 

 Linn.). Lvs. linear-lanceolate or spatu- 

 late, appearing after the fls. decay: spathe 

 long-acuminate, at length recurved and 

 twisted spirally, abomt 10 in. long, out- 

 side green, streaked purple ; inside dull 

 purple, spotted ; margins wavy : spadix 

 15 in. long. Spain. B.M. 2282. 



Pyr4mi,Eng. (I'scharumPyrdmi, Schott) . 

 Lvs. oblong above the middle, narrowing 

 abruptly to a very long petiole, resembling 



