But, as a matter of fact, there are species which are arrested; there are some that retrogress.

What had caused the man to retrogress Luis and Luise Obispo?

We don't stand still or retrogress; we keep going on and up.

Would I could retrogress over the devious and enchanting itinerary.

According to him the eyes of Proteus may develop to a certain point and then retrogress again.

In extremely exceptional instances the disease, after involving a small part, may retrogress and recovery take place.

That certain animals degenerate or retrogress in their development is susceptible of ready and familiar illustration.