240 The Maples and the Box-Elders. 



ing from 15 to 25 feet in height. It is rare in the lower district. 

 Further north it takes a larger growth, and it is found northward 

 as far as Southern New York. 



955. In the Western States, along the Mississippi and beyond, it 

 grows well, and it occurs out on the plains, in the timber belts that 

 fringe the rivers and streams, about as far west as any tree can be 

 found. 



956. Under its best conditions this tree grows to the height of 

 70 feet, but it is usually much less. It grows very rapidly, and 

 comes to maturity in from twenty to thirty years. It is among the best 

 of trees to cultivate for avenues and along public roads, and under 

 cultivation it has produced some varieties having bleached and yel- 

 lowish foliage, that gives it a fine appearance in ornamental planting. 



957. Although it prefers low rich grounds, it bears a drouth very 

 well, and in the more westerly states, on the borders of the Great 

 Plains, it deserves much attention as easily propagated, and likely 

 to succeed where many other kinds would fail. 



958. In the Western and Northwestern States, the sap of this 

 tree is made into sugar and syrup of excellent quality and flavor, 

 but less in amount than that from the sugar maple. 



959. As the staminate and pistilate flowers of the box elder grow 

 upon different trees, the seeds must be gathered in groves where 

 both kinds occur. The former are easily distinguished when in blos- 

 som by the stamens hanging in groups springing from common 

 points, by slender hairy stems, with four or five anthers at the end, 

 while the fertile blossoms show the rudiments of the future wings 

 of the seed, and have two pistils coming out between them. 



960. THE CALIFORNIA Box ELDER (Negundo Californiensis), 

 This is commonly a small tree, but rarely it grows to the height of 

 70 feet. It occurs along streams, following the coast range in Cal- 

 ifornia, from San Luis Obispo northward, but not into British Co- 

 lumbia. Its leaves are smaller and narrower than those of the other 

 species, and they are more coarsely toothed ; otherwise there is 

 much resemblance between them. 



THE LINDEN OR BASSWOOD FAMILY (Tiliacece). 



961. About thirty genera belong to this family, chiefly occurring 

 in the torrid and south temperate zones. They are mostly trees, 

 often of great size, with handsome flowers and foliage, a mucilagin- 



