468 THE CATKIN FAMILY. 



ing in a 1-celled fruit, wticli is either a 1-seeded nut, or a 

 several-seeded capsule opening in 2 valves. The catkin-scales, 

 or the inner scales, or both, usually persist, and are sometimes 

 enlarged into an involucre, either around or under the fruit. 

 Seeds without albumen, at least in the British genera. 



An extensive family, mdely distributed over the globe, but cliiefly in the 

 temperate regions of both hemispheres, where it often constitutes a large 

 proportion of the foi-est-trees. Minor differences, chiefly in the female 

 flowers, have induced its division into several tribes, often considered as inde- 

 pendent families, but as a whole it forms a natural as well as a distinct 

 group. Among the few British plants that have their inflorescence at all 

 resembling catkins, Hippophae is readily distinguished by the berry-Hke 

 fruits and scurfy foliage. Elms by their hermaphrodite flowers, and Conifers 

 by then' peculiar fohage independently of the important character of the 

 naked seeds. 



Tree or shrub, in flower. 

 Scales of the male catkins broad, imbricated. Anthers longer than 

 their filaments. 



Male and female catkins short, sessile, and erect 1. Gale. 



Male catkins cyUndrieal, usually pendulous. 



Three distinct flowers, each with 4 stamens, under each scale of 



the male catkins. Female catkins small, ovoid 2. Aldeb. 



Stamens 6 to 12 under each scale, not in distinct flowers. 

 Scales of the male catkins stalked. Female catkins cylindrical . 3. Birch. 

 Scales of the catkins sessile, 

 stamens at the base of the scale. Female catkins loose, with 



narrow scales 4. HoHNBEAM, 



Stamens on the scale itself. Female catkins sessile and bud- 

 like 5. Hazel. 



Scales of the male catkins narrow-linear, or divided, or very minute. 

 Anthers small, on slender filaments. 

 Flowers diiEcious. Catkins, both mate and female, cylindrical, com- 

 pact, and usually silky-hairy. 

 Catkin-scales entire. Stamens 2, rarely 3 to 5, with 1 or 2 gland- 

 like inner scales 8. Willow. 



Catkin-scales jagged. Stamens several, in an oblique, cup-shaped 



perianth 9. Poplab. 



Flowers monoBcioKS. 

 Male catkins slender and interrupted. Female flowers in small, 



sessile or shortly -stalked clusters 7. Oak. 



Male catkins globular, on pendulous stalks. Females erect, glo- 

 bular, softly hairy 6. Beech. 



Tree or shrub, in fruit. 

 Capsules (in catkins) opening in 2 valves. Seeds minute, with a tuft 

 of long, cottony hairs. 

 Scales of the catkin entire. Leaves on short or rather stiff stalks . 8. Willow. 

 Scales of the catkin jagged. Leaves on long stalks, very broad, shak- 

 ing with wind 9. Poplab. 



Nuts 1-seeded. 



Nuts small, in compact catkins. 



Nuts sUghtly succulent, and resinous outside 1. Galb. 



Nuts flat and quite dry. 



Scales of the catkins thin and deciduous. Nuts mnged ... 3. Biech. 

 Scales of the catkins hard, remaining after the nuts have fallen 3. Aldeb. 

 Nuts solitary, or in clusters, or in loose spikes, wholly or partially 

 enclosed in an involucre. 

 Nut small, in loose spikes, each in a 3-lobed, leafy involucre . . 4. Hosnbeam. 

 Nuts solitary or clustered, each in an involucre adhering to it at 



the base, with leafy, jagged lobes 5. Hazel. 



Nuts (acorns) projecting from a short, cup-shaped involucre . . 7. Oak. 

 Nuts completely enclosed in a prickly involucre 6. Beece. 



