366 CUPULIFERsE. [BETULA. 



80 ft., trunk 8-10 in. diam. ; bark flaking, silvery white; branches often 

 weeping (B. pen'dula, \VahJb.). Leaves 1-3 in., sometimes pubescent, rather 

 coriaceous, resinous or glandular when young ; petiole slender ; stipules 

 broad. Male catkins |-2 in., pendulous ; sepal 1 ; female spike solitary, 

 shorter, suberect. Scales of fruit cuneate, brown, 3-lobed to the middle. 

 Fruit orbicular, wing notched. DISTRIB. Europe (Arctic), N. Asia, N. 

 America (a variety). Bark used in tanning, and yields a fragrant oil ; juice 

 sugary in spring, and a wine is made from it ; wood durable. 



B. ALBA proper ; leaves truncate at the base, lateral lobes of fruiting bracts 

 spreading. JB. verruco'sa, Ehrh. 



Sub-sp. B. GLUTINO'SA, Fries ; sometimes bushy, leaves rhomboid- ovate, lateral 

 lobes of fruiting bracts erect. VAR. denuda'ta, leaves glabrous resinous. 

 VAR. pubes'cens, leaves and twigs pubescent. 



2. B, na'na, L. ; a bush, leaves short-petioled orbicular crenate, fruit 

 very narrowly winged. 

 Mts. of Northumbd., Peebles, and from Perth to Sutherland, local ; ascends 



to 2,700 ft. ; fl. May. Bush 1-3 ft. Leaves |-| in., glabrous, dark green. 



Catkins J the size of those of B. alba. Bracts of fruiting catkins broadly 



obcuneate, with 3 rounded lobes. DISTRIB. Arctic and Alpine N.W. and 



W. Europe, N. Asia, N. America. 



2. AL'NUS, Tournef. ALDER. 



Trees or shrubs. MALE fl. in catkins. Scales peltate, 3-fld. Sepals 

 and stamens 3-5 ; anth.ers 2-celled. FEMALE fl. in broadly ovoid spikes ; 

 scales fleshy, 2-3-fld., each with 2-3 bracteoles or sepals adnate to the 

 bract. Fruiting spike, woody ; fruit compressed, winged or not, 1-celled, 

 1 -seeded. Cotyledons flat. DISTRIB. Europe, Asia from the Himalaya 

 northd., N. America, Andes ; species 14. ETYM. The Latin name. 



A, glutino'sa, Gfcertn. ; leaves obovate- or orbicular-cuneate green on 



both sides, female spikes racemose. 



River-banks, marshes, &c., N. to Caithness ; ascends to 1,600 ft. in the High- 

 lands ; Ireland ; Channel Islands ; fl. March-April. A bush or tree, 20-40 

 very rarely 70 ft. ; trunk 1-2 ft. diam. ; bark black ; wood white when alive, 

 red when cut, then pale pink. Leaves 2-4 in., shortly petioled, glutinous 

 and hairy when young, sinuate and serrulate, laciniate in var. inci'sa ; sti- 

 pules ovate. Catkins appearing before the leaves ; male 2-4 in., bracts 

 orbicular red ; female spikes -1 in., terminal, racemose, obtuse, bracts red- 

 brown, woody. Fruit T V in., pale, hardly winged. DISTRIB. Europe, N. 

 Africa, W. and N. Asia. Wood soft, durable. 



3. QUER'CUS, Tournef. OAK. 



Trees ; buds scaly ; hairs often stellate. Leaves evergreen or deciduous ; 

 stipules deciduous. MALE fl. in catkins, wi f h usually a caducous bract at 

 the base. Calyx 4-7-lobed. Stamens indefinite (10 in the British sp.), 

 filaments slender exserted. FEMALE fl. spicate, enclosed in imbricating 

 bracts. Calyx-limb 3-8-lobed. Ovary 3-celled ; styles 3; ovules 2 in 



