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tirely closed in a prickly, irregularly ruptur- 
ing involucre.— bh. 
1. C. curysopoytta A. DC. — Tamalpais. 
Santa Cruz mountains. Summer. 
In Northern California a tall tree, in our lo- 
eal flora, a shrub. 
3. Corylus Tourn. Haze. 
Moneecious. Aments slender. Scales (bracts) 
imbricated. 6 flowers besides the scales 2- 
bracteolate. Stamens 8; anthers 1-celled. 
¢ flowers immersed into a bud; uppermost 
scales containing flowers, the rest empty. 
Ovary 2-bracteolate, crowned by a minute per- 
igonium, 2-celled; stigmas 2. Fruit a nut, sur- 
rounded by a large incised involucre, formed 
by the growth of the two bractlets.— ». 
1. C. rostrata Ait.—Common. Spring. 
Family 2, BETULACEZ. 
Hypogynous. ¢ ament: bracts shield-shap- 
ed, each enclosing 3 flowers with minute peri- 
gonium and four stamens. ¢ aments: bracts 
3-lobed, each enclosing 3 naked flowers; 
ovary 2-celled; cells l-ovulate; styles 0; stig- 
mas 2. Fruit an akene (nutlet) affixed to the 
lignescent bract, and collected into a strobi- 
laceous inflorescence. 
1, Alnus Tourn. ALpzER. 
Fruit lignescent; nutlets attached to lignes- 
cent bracts on a lignescent axis.— 2. 
