Realistic, "Blended" Gryphon

OK, why is there a 'griffin' catagory and a 'gryphon' catagory?

Stratadrake posted a challenge thread on the request forum, and the first one was to create a "blended" version of a mythological creature such as a gryphon. I sketched out the initial concept in class, and transfered it into my sketchbook after.

I figured that real animals do not have six limbs, so neither should my gryphon. It's a predator, and it's powerful legs allow it to run quickly after prey. It's flightless, but it's wings allow it to jump long distances or onto the backs of larger prey, which it usually goes after in packs.

Male gryphons have a tall crest which helps to attract females, the females, however, have no crest. Both do have tufts of feathers located behind their ears, echoing the pointed ears of a large cat. They have a toothed muzzle rather than a beak, and their feet resemble feline paws rather than the taloned feet of other birds, but their entire bodys are covered in feathers, with the scaly skin typical of bird feet over their 'paws.' on the lower legs there are long, fur-like feathers like Snowy Owls have. They are large birds, standing about four feet tall on average at the shoulder.

If you like him, I've put up a CG colored version. It's cool.

And I now realize that I misspelled 'gryphon' when I was doing the fancy lettering. I feel stupid now.