n8 A TEXT-BOOK OF BOTANY. 



A manna is also yielded by Cedrus Libani and Larix decidua. The 

 latter is known as " Briancon Manna," and contains melizitose. 

 The bark of some species furnishes valuable tanning material, as 

 that of the hemlock spruce (Tsuga canadensis). 



Thuii 



FIG. 76. Fruiting twig of common Juniper (Juniperus communis), of Red Cedar or 

 Savin (Juniperus virginiana), and young twig of White Cedar or Arbor Vitae (Thuja occiden- 

 talis). From "Minnesota Trees and Shrubs," 



The Coni ferae yield large quantities of volatile oils, resins, and 

 allied products which are used both in medicine and the arts. 

 A number of them yield turpentine (see Vol. II)- Larix decidua 

 of the Alps and Carpathian mountains yields Venice turpentine. 

 Abies balsamea is the source of Canada turpentine or balsam of 



