"Ratha and her clan, the Named, are sentient prehistoric big cats. In Ratha's Courage, the first book about the Named since 1994, Ratha extends the use of the Red Tongue—fire—to a hunter tribe. One of the hunters ignites a blaze that sets off a devastating conflict between the two clans. Now Ratha must find the courage within herself to set it right."I've honestly never heard of these books, although they sound interesting. The series is set in the ancient past and features several prehistoric mammals. That creature the cat is riding on is almost certainly an Indricotherium, the largest land mammal that ever lived. Apparently several of the original books have been republished so readers can see where it all started.
The books are written for young adults, so you will most likely find them in the children's section of your local bookstore. I really can't say anything more about the novels, but the author writes on her web site that the fictional species of the series is evolved from Dinaelurus, which was a cat-like nimravid rather than a true cat.
Ratha's Courage is scheduled for release on Oct. 18, but it looks like the reissued novels may be out in stores now.
The official web site of the series is www.rathascourage.com