Comprehensive

a.
  1. Including much; comprising many things; having a wide scope or a full view.
  2. Having the power to comprehend or understand many things.
  3. (Zoöl.) Possessing peculiarities that are characteristic of several diverse groups.

The term is applied chiefly to early fossil groups which have a combination of structures that appear in more fully developed or specialized forms in later groups. Synthetic, as used by Agassiz, is nearly synonymous.