Dividing up my creatures

I had a revelation about my dinosaur series. As much as I would like to give each of my fictional reverse engineered creatures an appearance of some kind in my first book, I feel like it may be too much for my readers. With this in mind, I am thinking of dedicating the first volume on just the dinosaurs, the second volume on the new terrestrial lifeforms, and the third on the marine lifeforms. After that, who knows? This would be a good idea considering I have made up to fifteen different dinosaur species and three dozen non-dinosaur species aside. I have been busy coming up with the creatures of this new series.