A. Leaves few, in sheathed bundles, set spirally on the twig.
THE PINES.
AA. Leaves solitary, set spirally on the twig.
B. Twigs with bracket-like projections for attachment of leaves;
cones hanging down.
C. Leaves flat, blunt, with short stalks.
The Hemlocks.
CC. Leaves angled, sharp, without stalks.
The Spruces.
BB. Twigs smooth; cones standing erect.
The Firs.