PART II 

 PINACE^ 



ABIES, Linnaeus. 

 Silver Firs, 



Evergreen trees confined to the temperate regions of the 

 northern hemisphere, but widely distributed in Europe, N. Africa, 

 Asia, from the Himalaya northwards, and North America. In the 

 more northerly latitudes they occur at sea-level but at a consider- 

 able elevation in Central and S. Europe, the Himalaya, N. Africa, 

 Mexico, and W. North America. 



Young trees are of pyramidal or cylindrical outline with the 

 branches more or less regularly whorled, forming flat sjjrays, each 

 whorl usually marking one year's growth. The trunks of mature 

 trees taper very gradually in the forest and are clear of branches for 

 a considerable height, but in the open rapidly decrease in girth 

 and retain the branches low on the trunk. Bark of young trees 

 smooth or beset with resin bUsters ; in old trees deeply furrowed 

 at the base. Young shoots smooth or grooved, with or without 

 down, marked at the base by persistent bud scales of the previous 

 year. Winter buds ovate or oblong, blunt or pointed, resinous 

 or non-resinous ; the terminal bud of the main axis surrounded 

 by four or five secondary buds, three buds terminating the 

 branches. Leaves variously arranged on the branchlets, according 

 to species, those on lateral shoots either pectinate, spreading all 

 round the shoot or crowded and directed forwards in overlapping 

 ranks ; on leading shoots widely spreading and on coning branches 

 directed upwards. The leaves are dark green, pale green or 

 glaucous, linear, rounded or short-pointed, but usually notched 

 at the apex ; flattened, rarely four-angled, marked below with 

 two waxy bands of stomata, sometimes with a few stomata on 

 the upper surface, especially on the uppermost shoots. Each 

 leaf is traversed by two resin ducts which are either marginal or 

 median. Bruised leaves emit an odour of turpentine. The foliage 

 persists several years and on falling leaves circular, disc-like scars 

 on the shoots. Male and female floivers borne on the same tree 

 in spring. 3Iale floivers in short catkins from the leaf axils on the 

 under-side of the branchlets which, on falling, leave gall-like scars. 

 Female floivers in cones composed of numerous bracts each bearing 



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