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BETULACEAE 
Leaflets usually 7 to 9, almost entire; husk (when dry) falling away from the 
thin-shelled nut..3. J. regia. 
1. J. californica Wats. Southern California Black Walnut. 
Tree 4.3 to 8.6 m. high, commonly with several stems from the base, the 
crown much broader than high; leaflets 11 to 19, oblong-lanceolate, ser¬ 
rate.—Coastal S. Cal. 
2. J. hindsiijepson. California Black Walnut. Tree 8 to 18 m. 
high, with a single erect trunk, the crown much higher than broad; leaflets 
lanceolate, 7.2 to 12 cm. long’—Central Cal., on old Indian camp-sites. 
It is extensively used as a stock-graft for English Walnut. 
3. J. regia L. English Walnut. Tree 5 to 11 m. high; leaflets 5 to 
13, oval, almost entire.—Cult, from Asia and more properly known as 
Persian Walnut. The annual crop in Cal. is about 52 million pounds. 
MYRICACEAE. SWEET-GALE FAMILY 
Shrubs or small trees. Leaves alternate, simple, resinous-dotted. 
Flowers unisexual, in catkins. Perianth none. Stamens 4 to 16. Ovary 
superior, 1-celled; ovule 1; stigmas 1 to 4. Fruit a nutlet.—Species about 
50, mostly tropical. 
1. MYRICA L. 
The only genus. (Greek murike, the ancient name of the Tamarisk.) 
1. M. californica Cham. Wax Myrtle. Densely branched shrub or 
small tree 2 to 8 m. high; leaves oblong or oblanceolate-oblong, dark 
green, glossy, 5 to 12 cm. long; fruit berry-like, coated with a white wax. 
—Sand-dunes, moist flats or hillsides, near the ocean. 
BETULACEAE. BIRCH FAMILY 
Ours trees with alternate simple leaves and small flowers in clustered 
catkins. Staminate catkins pendulous, the flowers 3 in the axil of each 
bract and consisting of a membranous 4-parted calyx and 2 to 4 stamens. 
Pistillate catkins much smaller and shorter, sub-erect, the flowers 2 in 
the axil of each bract, without perianth, consisting of a pistil with 2 
styles and a 2-celled ovary. Fruit a small flattened 1-seeded margined 
or winged nut.—Species 75, extra-tropical northern hemisphere. 
1. ALNUS Hill. Alder 
Pistillate catkins woody and cone-like in fruit. (The Latin name.) 
Leaf-margin plane, with small scattered glandular teeth ; stamens 2, sometimes 3, 
1 or 4...1. A. rhombifolia. 
Leaf-margin coarsely toothed, the entire margin with a narrow underturned 
edge; stamens 4, rarely 3.2. A. rubra. 
1. A. rhombifolia Nutt. Tree 5 to 20 m. high, the trunk brown or 
ashy-gray; leaves narrowed to each end from the middle, varying to 
ovate or elliptic; bracts of staminate catkins obtuse; stamens 2 to 4.— 
Interior streams, in valleys or canons, s. to S. Cal. The wood is used 
for making boxes, the slender trunks for studs and rafters. 
2. A. rubra Nutt. Tree 8 to 17 m. high, the trunk gray or white; 
leaves 4.8 to 14.4 cm. long, broadly ovate, often rusty beneath, the margin 
toothed and serrulate and commonly revolute; bracts of the staminate 
