Easy Sizing Chart

Pixies are smaller than Hobbits
and Elves are taller than Kelpies.
With that Gnomes are smaller than Bunyips
and Fauns are taller than Dwarfs.
So larger small Dragons are bigger than a Centaur,
and a Stoor Worm is larger than a Merman.
Thus Orcs are shorter than your average Gryphon,
So how big is a shorter tall Selkie?