Emotions and facial expressions. Shown right from the get-go here (Chapter 2 of Jack Hamm's "Cartooning the Heads and Figure") through line and brush work here as much as the cartoons themselves. Some really gorgeous stuff.
Anger. Fear. Surprise. Sorrow. Yelling. Worrying. Thinking. Smiling. Laughing - with tongues, teeth and (my favorite by far) plain openings. :)
Hamm goes on to who the emotive qualities of the eyelids. If only Jim Davis had learned, there's more than one facial expression. Ah, t'would have been a different world.
And just check out his "alphabetized catalog of emotions and expressions (with cross references)". I remember sitting at the kitchen table with bros. David, Richard and Mike going through exercises just like this. David must have seen a copy of this book somewhere.
Today finishes off with "Muscles of Expression". Remember kiddoes, you can't cartoon something if you don't understand it's real structure. Only a great comedian can do great drama. Only a clown can make you cry.
Ooooooooooooooooo, there's plenty more-a-comin', don't you fret.
Talk to you soon.