THE MORE IMPORTANT PLANT PRODUCTS 65 



slightly pointed, and perfectly smooth on the outside. These 

 two trees have been very much confused by botanists, and 

 it is well to emphasize their distinctive characters. The 

 " T'ung-yu " is the more hardy tree of the two, and is much 

 more widely distributed, furnishing fully nine-tenths of the 

 so-called " wood oil " used in China and exported from thence. 

 Within the last decade " wood oil " has attracted considerable 

 attention in Europe and in the United States of America as a 

 possible substitute for linseed oil, and it is annually imported 

 into these countries in vastly increasing quantities. Chemists 

 have investigated the products of these two trees, and find no 

 appreciable difference in the oils. 



The " Mu-yu " {A. montana) is common in the regions 

 around Wuchou to the west of Canton, where it is chiefly 

 used, and from whence it is exported to Hongkong and else- 

 where. The trade is not large ; in igio it was estimated at 

 53,106 piculs.i 



The " T'ung-yu " {A. Fordii) is abundant throughout the 

 Yangtsze Valley from Ichang westwards to Chungking ; more 

 especially it luxuriates in the region of the gorges and the 

 contiguous hilly country up to 2500 feet altitude. It is 

 essentially a hillside plant, thriving in the most rocky situations, 

 and on the poorest of soils, where there is a minimum rainfall 

 of 29 inches ; it will also withstand drought and a few degrees 

 of frost. It is a quick-growing tree, seldom exceeding 25 feet 

 in height and averaging less, with a much-branched, fiat-topped 

 head, 15 to 30 feet or more through, and is highly ornamental in 

 flower and foliage. The flowers, produced in great profusion 

 during April, are white, stained with pink and yellow markings, 

 especially near the base. These are always followed by green, 

 apple-like fruits, which ripen in September and are hidden 

 amongst the large, glossy-green, heart-shaped leaves. Each 

 fruit contains three to five seeds, which somewhat resemble 

 shelled Brazil-nuts, but are much smaller. 



The fruits break naturally in three parts when dead ripe, 

 but they are invariably gathered before this period, and collected 

 into heaps which are covered with straw or grass. Fermenta- 

 tion sets in and quickly disposes of the thin fleshy part of the 



1 One picul equals 133^ lbs. 

 VOL. II. — 5 



