Different “Subspecies” for Ferroic Phases Derived from a Common Prototype and Belonging to the Same Species

The concept of “subspecies” is introduced as convenient for investigating transition between isogenous ferroic phases (i.e., ferroic phases derived from a common prototype) and some other subjects. Examples of isogenous ferroic phases belonging to the same species and different subspecies are presented and discussed. All the species each divisible into more than one subspecies and all these subspecies are determined and tabulated.