The Firvulag are generally squat, solid, humanoid aliens that look very similar to humans from Julian May's Galactic Milieu universe. They originate from a distant galaxy, but have fled from their home planet to the Pliocene period of Earth via an FTL living ship along with a co-genetive species called the Tanu. They can come in a range of sizes from human child size to veritable giants, but most are slightly smaller than the average human and tend to be more rotund.