THE PLANT WORLD. 11 



sects to cardboard. Cherry tree giiui makes a thick, useful mucilage. 

 Certain seeds, as ([uince, marsh-maHow, linseed, infused in boiling 

 water, make good mucilages. 



(jum-resin contains rosin mixed with an essential oil, usually with 

 a small amount of mineral water solul)le in alcohol. It is opaque and 

 o-enerallv ))rittlc. (utUxmnm is such a oum -resin, obtained from stems 

 of several plants belonging to the parsley family, growing in western 

 Asia. They have strong roots, stems from 3 to 6 feet high, finely 

 divided leaves, and large umi)els of yellow flowers. A little above the 

 ground, the stem is cut; a milky juice exudes, hardens on exposure to 

 the air, and has a balsamic fragrance. It is used in medicine. Gam- 

 ho<ir is a gum-resin from Ceylon, obtained from species of Garcinia. 

 It is used in painting, chiefly with water colors, also for brass lacquer- 

 ing. An allied species yields oil and butter. 



Brurcohi is a gum-resin obtained from Sfi/i-f.r /)rf).7(>hi, a member 

 of the storax family, native to Sumatra, but found in other tropical 

 reo-ions. It is a vellowish iuice, obtained from incisions in the stem. 

 The gum is valual)le in perfumery and medicine. One species, /S. 

 ]>niictafiim, yields its gum after the tree has been cut down and suffered 

 to lie for many years, The bark is then taken off, and the gum found 

 in little lumps underneath. This is used for frankincense. Storax 

 o/;^V/;/r/Z/'.v is obtained from another species, from Asia Minor, only from 

 a tree fully grown. 



Ammoniaeiiiii, (ixafixfida^ Ix/rlUmn^ (')[ph(>rh>vin^ fviinhincense and 

 iinjrrh are examples of gum-resins. The myrrh of the Bible, one of 

 the precious offerings of the Magi to the infant Jesus, was perhaps a 

 mixture of the gummy exudation of a species of Rock-rose or Cistus, 

 and a sticky, white gum from Balmmodendron myfrha, a small tree 

 trrowinof on the coast of Africa. I)Oth are fragrant, and are in use 

 to-day in perfumes. 



Balsavii< are fragrant resins, or resins mixed with volatile oils, 

 containing benzoic and cinnamic acids, used in medicine and the arts. 

 Copaiva and Peru balsams are examples. The former is obtained from 

 a member of the l)ean family, a hard wooded tree of considerable size, 

 found in the forests of South America. The liquid basam collects in 

 the veins of the plant in such quantities, that it often bursts with a 

 loud report. The native collector cuts a large hole in the tree, often 

 one foot square. Then he strikes the tree heavily with an axe, above 

 the hole; the liquid rushes out wnth great force, and with a gurgling 



