272 MYRICACEAE • BETULACEAE 



M YRI CA — continued 



M. californica. Californian Wax Myrtle. 15. May-June. E. Ls. lane, 4, 

 leathery, toothed, glossy green. Fruits small, round, thinly coated with 

 white wax. California. (Fig. 106 E.) 



M. cerifera. Wax Myrtle. 40. March- April. \ E. Ls. lane, 3, thin, toothed 

 towards apex, glossy green above. Fruits small, round, thickly coated 

 with white wax, in clusters on old wood. U.S.A. (Fig. 106 F.) 



M. Gale. Sweet Gale, Bog Myrtle. 4. March-April. D. Ls. oblanc, 2, 

 toothed towards apex, dark glossy green. Fruit small, 3 -pointed, resin- 

 dotted, in dense catkins up to | long. Northern Hemisphere (including 

 Britain). (Fig. 106 D.) 



Family 98. BETULACEAE. P4 or o, A2-4, G (2) 



Ls. alternate, stipulate, usually straight-veined. Fls. in male and female catkins. 

 Fruit a i -seeded nut. I 



ALNUS. Alder. Stamens four. Female catkins become erect woody cones in 



fruit. 



A. cordata. Italian Alder. 80. March. D. Branchlets angled, hairless. Ls. 



broadly ov., 4, pointed, straight or heart-shaped base, finely and evenly 



toothed, veins curved, dark glossy green above, hairless except for tufts 



in vein-axils below. South Europe. (Fig. 106 H.) 



A.firma. 30. March. D. Branchlets hairless. Ls. ov., 4, pointed, finely and 



doubly toothed, 12-26 pairs parallel veins. Japan. 

 A. gliitinosa. Common Alder. 90. January-February. D. Branchlets clammy, 

 hairless; buds stalked. Ls. broadly obov., or circular, 4, coarsely toothed, 

 rounded or notched at end, dark glossy green and clammy above, pale 

 green below. Europe (including Britain), North Africa, North and West 

 Asia. (Fig. 106 G.) « 



Variety imperialis. Ls. cut into linear lobes. (Fig. 34 F.) | 



Variety laciniata. Ls. deeply and pinnately lobed. (Fig. 34 G.) 

 A. incana. Grey Alder, Speckled Alder. 70. Branchlets downy. Ls. ov., 4, 

 pointed, double-toothed and slightly lobed, glaucous or grey-green below. 

 Cones stalkless or nearly so. North temperate regions. (Fig. 106 K.) 

 Variety aurea. Ls. yellow. 

 Variety glaiica. Ls. blue-green below. 

 Variety incisa. Ls. deeply lobed, lobes toothed. 

 Variety pendula. Weeping form. 

 ^./(^pornVa. Japanese Alder. 80. February. D. Ls. lane, 5, tapered at both 



ends, finely toothed, dark glossy green. Japan. 

 A. nitida. Himalayan Alder. 100. September. D. Ls. ov., 6, long-pointed, 

 coarsely toothed or almost entire, glossy green above, pale green below. 

 Himalaya. (Fig. 106 j.) 

 A. oregona {A. rubra). Oregon Alder. 50. February. D. Young shoots 

 angled, hairless. Ls. ov., 6, margins recurved, 10-15 pairs parallel veins, 

 dark green above, pale or greyish below, edged with small toothed 

 lobes, l.-stalk and veins red or yellow. West North America. (Fig. 106 L.) 



BETULA. Birch. Ls. ov., usually pointed, sharply and unevenly toothed, 



