508 . Select Plants for Industrial Culture 



Pycnanthemum incanum, Michaux. 



North- America. A perennial herb, in odor resembling both Penny- 

 royal and Spearmint. It likes to grow on rocky woodland, and on 

 such it might be easily naturalized. 



Pycnanthemum montanum, Michaux. 



The Mountain-Mint of North -America. A perennial herb of 

 pleasant, aromatic, mint-like taste. These two particular species 

 have been chosen from several North-American kinds to demonstrate, 

 that we may add by their introduction to the variety of our odorous 

 garden-herbs. They may also be subjected with advantage to 

 distillation. 



Pyrularia edulis, Meissner. 



Nepal. Khasia, Sikkim. A large umbrageous tree. The drupa- 

 ceous fruit is used by the inhabitants for food. A few other species 

 occur in Upper India, one on the high mountains of Ceylon, and one 

 in North-America. The latter, P. pubera (Michaux), can be utilized 

 for the oil of its nuts. 



Pyrus aucuparia, Gaertner. 



Europe, Northern and Middle Asia. The Rowan or Mountain- 

 Ash. Height seldom over 30 feet. Wood particularly valuable for 

 machinery and pottery-work, also crates. 



Pyrus coronaria, Lmn4. 



The Crab-Apple of North-America. This showy species is 

 mentioned here as worthy of trial-culture, since it is likely that it 

 would serve well as stock for grafting. Best grown in glades. 

 Wood nearly as tough for screw- work as that of the pear-tree 

 (Robb). 



Pyrus communis, Linn4. 



The Pear-tree. Middle and Southern Europe, Western Asia. 

 Well known even at the time of Homer; and many varieties were 

 cultivated in Italy at the commencement of the Christian era; pears 

 were available also to the lacustrine people of Switzerland, Lombardy 

 and Savoy, but seemingly not so extensively as the apple. Prof. C. 

 Koch regards the Chinese Pyrus Achras (Gaertner), which is the 

 oldest name for P. Chinensis of Desfontaines and Lindley, as the 

 wild plant, from which all our cultivated varieties of pears have 

 originated. The pear-tree is cultivated iip to 10,000 feet in the 

 Himalayas; like the apple-tree, it sets no fruit in tropical regions, 

 but on the other hand it will bear a good deal of frost, being grown 

 in Norway to lat. 63 52'. The tree attains an age of over three 

 hundred years, fully bearing. At Yarmouth, a tree over 100 

 years old has borne as many as 26,800 pears annually; the circum- 

 ference of its crown is 126 feet (Masters). Pear-wood is used 

 by wood-engravers, turners and instrument-makers. A bitter gly- 

 cosid, namely phlorrhizin, is attainable from the bark of apple- and 





