f.J2 SCOTCH PINE. 



leaves, terminal buds, male and female flowers, year- 

 old and two-year-old cones, preserved in alcohol ; 

 mature cones and seeds, dry ; alcohol ; potash ; glycer- 

 ine ; sulphuric acid ; and if convenient, magenta ; 

 methyl blue ; and chlor-iodide of zinc. 



LABORATORY WORK. 

 GROSS ANATOMY. 



A. GENERAL CHARACTERS. Note 



1. The central axis or stem; its few main branches and 

 numerous very short dwarf branches * bearing 



2. Pairs of very slender elongated green needle leaves, 



3. The scales upon the stem, those covering the buds at 

 the apex of the stem and those overlapping the bases of 

 young leaves. All may be called scale leaves. 



4. Near the base of the young shoots in some specimens, 

 a number of oblong (nearly globular) clusters of light 

 yellow bodies, stamens, the male flowers ; in other 

 specimens, one or two small oval clusters of female 

 flowers, projecting beyond the end of the stem. 



B. THE STEM. Examine 



1. The surface of a year-old shoot. Note the scales 

 covering it, especially near the base of the shoot. 

 Compare with the surface of older stems ; note the 

 gradual obliteration of the scales. 



2. The arrangement of the main brnches? Note the 



1 The terms " dwarf branches " or "dwarf shoots" will be used to 

 distinguish these from the main branches or shoots. (The term shoot 

 includes the branch with its leaves.) 



2 Best seen in specime'ns from young vigorous trees. If possible the 

 student should study the tree itself. 



