The terms "eogenesis," "telogenesis," and "mesogenesis" are not standard scientific terms in biology or other fields. They are not commonly used to describe any specific processes or stages of development.

It's possible that these terms are being used in a specific context or theory that you are not providing. To understand their meaning, it would be helpful if you could provide more information about:

* Where did you encounter these terms? (e.g., a specific book, article, website)

* What was the context of their use? (e.g., a discussion about evolution, development, or another topic)

With more information, I can help you understand the intended meaning of these terms.