EXOGENOUS SERIES-BROADLEAF WOODS. 87 



ancients, because it was light and tough and would indent 

 without breaking. The wood is often substituted for white- 

 wood, but is less desirable, although valuable as a basis for 

 paper-pulp. The trees may be known by the long drooping 

 catkins that appear early in the spring before the leaves, and 

 that are followed by white downy seeds that soon escape to 

 whiten the surrounding ground. The poplars are noted for 

 foliage more or less constantly in agitation. This peculiarity, 

 so pronounced in the aspen (Populus tremuloides), is due to 

 the very long petioles or leaf-stems. The cottonwoods abound 

 in many otherwise arid regions of American Western deserts. 

 The balsam poplar (Populus balsamifera) which thrives far into 

 the North, was said, by Sir John Franklin, to form much of the 

 drift seen by him upon the shores of the Arctic Sea. The bal- 

 sam poplar must not be confused with the true balsam, Abies 

 balsamea (pp. 162-163), although both are called Balm of 

 Gilead. Sudworth enumerates twelve distinct species of the 

 genus Populus that grow in the United States. 



The cucumber trees are of the magnolia family and grow 

 in many of the Eastern States. The wood resembles and is 

 probably often mistaken for whitewood, for which it is a fair 

 substitute. The trees may be known by their fruit, which 

 resembles vegetable cucumbers. Magnolia is from Magnol, a 

 botanist of the seventeenth century. 



Basswood is a name applied to trees known in Europe and 

 America as limes, lime trees, lind, linden, tiel, tiel trees, 

 bass, and basswood trees. The trees and their wood were 

 early esteemed, the first for their shade and appearance, and 

 the last for their working qualities, which resemble, but are 

 inferior to, whitewood.* The trees are characterized by their 

 dense foliage and clusters of small cream-colored fragrant 

 flowers, so attractive to bees as to have originated the further 

 name bee-tree. Tilia arises from the ancient name for these 

 trees. 



* The carvings of Gibbons, a famous English artist, are said to have been made 

 entirely of linden, no other available wood being so even-grained and free from 

 knots. 



