a long sentence

[judytu]

"They were all healthy, thoughtless young animals, sleek, graceful, high-spirited, the boys as mettlesome as the horses they rode, mettlesome and dangerous but, withal, sweet-tempered to those who knew how to handle them."

This is a selection from Gone with the Wind. It is a long sentence puzzling me.

Why there is not a comma preceding thoughtless, that is to say, they were all healthy and thoughtless young animals, sleek, graceful, high-spirited?

[Joe]

"They were all healthy, thoughtless young animals, sleek, graceful, high-spirited, the boys as mettlesome as the horses they rode, mettlesome and dangerous but, withal, sweet-tempered to those who knew how to handle them."
Why there is not a comma preceding thoughtless...?

But there IS a comma preceding "thoughtless".

[judytu]

Ah, embarrassing. Why there is a comma but not "and"

[Joe]

There is no rule that says that adjectives before a noun have to be separated by "and", except to avoid ambiguity or for two colours, eg:
She was wearing a long, blue and yellow dress.
compare
She was wearing a long, blue, silk dress.

[judytu]

Oh I see. Thank you very much.