THE AMERICAN BOTANIST. 55 



Wood Production. — A few years ago, people spoke of 

 "our inexhaustible forests;" they do not do so nowadays. 

 Our country is still sparsely settled in comparison with many 

 European countries but with characteristic extravagance, we 

 have wasted the forests more than many a larger nation would 

 have done. At present we are removing annually twenty-three 

 billion cubic feet of wood. According to the National Geogra- 

 phic Magazine we use 100,000,000 cords of fire-wood; 

 40,000,000,000 feet of lumber; 1,000,000,000 posts and poles; 

 118,000,000 ties; 1,500,000,000 staves; 133,000,000 sets of 

 heading; 500,000,000 barrel hoops; 3,000,000 cords of pulp 

 wood; 165,000,000 cubic feet of round mine timbers and 

 1,250,000 cords of wood for distillation. Other nations are 

 managing their forests in such a way that the annual increase 

 of growth balances the wood removed. Unless we quickly 

 adopt the same policy we will soon be dependent upon these 

 more provident people for what wood we use. 



Hairs of Dicksonia. — The boulder fern {Dicksonia 

 pilosiuscula) is frequently called hairy dicksonia, fine-haired 

 mountain fern and other names of similar import to indi- 

 cate its vestiture of hairs ; indeed, the specific name here used 

 also refers to the fact that the fronds are hairy. Going fur- 

 ther we find that these hairs, or rather one of their qualities, 

 is responsible for several other common names of the plant for 

 the etherial oil which they secrete gives it the fragrance which 

 has caused it to be named hay-scented fern, sweet-grass fern, 

 sweet fern and the like. Microscopic examination of the leaf 

 surface shows that the frond bears two kinds of hairs, acicular 

 and glandular. The acicular hairs are simply pointed, but the 

 glandular ones are terminated by a bulb-like swelling from 

 which the fragrant and volatile oil is exhaled. The glandular 

 hairs are most abundant on plants grown in dry sunny places, 

 following the rule for vegetation in general in this respect. Ac- 

 cording to C. E. Waters the oil distilled from this plant has a 



