Group 16

Leaves Opposite

Simple Or 1−Foliolate, Toothed Or Lobed

Lobed With A Few Irregular Teeth

Leaves Regularly Toothed or Crenate; Stipules Present (Visible On Young Shoots)

Stipules Interpetiolar

Stipules Free or Encircling Stem, Not Interpetiolar

Stipules Absent

Leaves With Numerous Surface Glands

Leaves Leathery and With Stiff Teeth

Petioles Usually More Than 8 mm long

Petioles Regularly Less Than 8 mm long

1−Foliolate: Opposite, Margins Entire; Mostly With Distinct Oil Dots

Leaves Aromatic When Crushed

Leaves Not Aromatic When Crushed

Entire With Distinct Oil Dots

Strongly 3−Veined From The Base

Lower Surface Of Mature Leaves Hairless (Or Almost So)

Lower Surface Of Mature Leaves Hoary

Lower Surface Of Mature Leaves Distinctly Hairy

Leaves With Intramarginal Vein Present, Bluntly Pointed or With An Abrupt Point

Leaves Mostly Large, Usually More Than 5 cm Long

Leaves Mostly Small, Usually Less Than 5 cm Long

Intramarginal Vein Present, Young Stems Hairy

Intramarginal Vein Present, Stems and Leaves Hairless

Oil Dots Obscure or Very Sparse

Translucent Dots Distinct; Leaves Mostly Narrow and Long, Lateral veins Very Numerous

Translucent Dots Distinct; Leaves Broader and Drawn Out To A Short Point

Leaves Drawn Out To A Long Point.

Lateral Veins Usually 12 to 20 Pairs

Lateral Veins Less Than 12

No Intramarginal Vein, Not 3−Veined From The Base

Leaves Aromatic When Crushed

Leaves Not Aromatic When Crushed

Group 17

Oil Dots Absent

Stipules Present

Either As Free Small Stipules or Pairs Of Interpetiolar Stipules or As A Sheathing Cap Over The Terminal Bud

Domatia Always present

Domatia Present In Some Laeves Only

Domatia Always Absent

Stipules Interpetiolar

Stipules Free or Encircling Stem

Oil Dots Absent, Domatia Present, Stipules Absent, Intramarginal Veins Present, Milky Latex Present

Milky Latex Present

Milky Latex Present and Axillary Spines

Domatia Present

Leaves With 3 or More Veins From Near Base

Intramarginal Veins Present

Stipules Absent and Lacking Domatia, Milky Latex and Extra Longitudinal Veins

Densely And Softly Hairy Below

Hairless, Bark And Twigs Pulling Away In Long Strips, Very Tough

More Or Less Hairless, Bark On Twigs Not Pulling Away In Long Strips; Leaves Leathery To Stiff

More Or Less Hairless, Bark On Twigs Not Pulling Away In Long Strips, Leaves Soft To Firm

Leaves Usually Less Than 5 cm Long