"H. BOTANY AND HORTICULTURE. 281 



may form lenses, through which the rays of the sun may be 

 concentrated, and act upon the inflammable surroundings, 

 and thereby set Are to them. In many cases, possibly, a vapor 

 of escaping turpentine may also, by its combustibility, cause 

 the fire to spread with greater rapidity. \B,Aug. 14, 114. 



THE AILANTHUS-TREE. 



The disagreeable smell of the ailanthus-tree while in blos- 

 som need be no objection to the planting of it on a large scale 

 as a timber tree, since, as is well known, it is dioecious, and the 

 male tree alone possesses the unpleasant peculiarity. It is 

 only necessary to propagate the female tree, therefore, in or- 

 der to have an equally fine grove without the practical in- 

 convenience referred to. It so happened that, on the first in- 

 troduction of the tree into this country, the male tree alone 

 was propagated. The female, however, is coming more rap- 

 idly into use, and may readily be known by the clusters of 

 seeds it bears, similar to those of some species of the ash 

 family. 



There are few trees more valuable for timber than the ai- 

 1 an thus. The wood has much of the same properties as the 

 chestnut, and is equally durable, grows with as great rapid- 

 ity, and in its native country obtains a height of between two 

 and three hundred feet. It is said to be well adapted to 

 growth on the Western prairies, and will undoubtedly per- 

 form an important part in clothing them with forest vegeta- 

 tion. 



CINCHONA IX JAVA. 



According to Professor Hasskarl, the cultivation of cin- 

 chona in Java continues to be a success, the weather having 

 been favorable and the growth of the plant perfectly satis- 

 factory. The number of plants obtained from seeds and lay- 

 ers was aboutfone and a half millions, principally of the spe- 

 cies C. calisaya ; eight hundred and seventy thousand were 

 transplanted in addition, and over one thousand pounds of 

 the dry bark were sent to Holland in 1869, bringing from 

 thirty-six to fifty-four cents per pound. The total product 

 of 1870 is estimated at eight thousand eight hundred pounds 

 for exportation, besides some hundreds for home use in the 

 island. 12 A, December 8, 1870, 114. 



