Consider the alligator. Or at least, consider considering the alligator. What the National Geographic Society did for, and with, sharks and pandas and lions, it attempts to do tonight for and with the ancient, slithery, guiltily smiling reptile. Such a world that has such creatures in it.

"Realm of the Alligator," at 8 on Channel 26, was shot among the 700 square miles of the Okefenokee Swamp, most of which, we are told, lies in southeast Georgia, not Florida, as is widely assumed. Here, snakes stalk woodpeckers, plants eat bees, bugs buzz, turtles worry, and the alligator rules with surreptitious savoir-faire.

Talk about your primordial ooze. There's plenty of it oozing on this, the last of the season's four new Geographic Society specials. One may have no burning desire to visit a swamp (and it's a burning swamp after lightning strikes it), but since the cinematography on this special is up to the Geographic's standard, which is to say outstanding, the swamp becomes just the place to spend an astounded hour.

A dragonfly's head is captured in eerie macro-close-up. Little baby red-belly turtles emerge from mother's womb and scramble into the water. A corn snake slithers up a tree in pursuit of a bird and cameras snare it from several angles, one of them a literal bird's-eye view. Underwater, a baby alligator waits for a katydid to reach just the right spot and, zap, it's a snack. In elegant slow motion, a grown alligator does the same thing to a passing snake.

Music and narration, the latter capably handled by Pernell Roberts, are used with skillful economy; the sound track is given over instead to the noises and voices of the swamp, including the low moan of mating gators, the cluck-cluck of a marine biologist who has mastered a gator call and the mournful buzz of that imprisoned bee whom the wily plant hath entrapped.

John Paling produced and helped photograph this special. Alan Degan and Joe Seamans did most of the photography. Nicolas Noxon wrote just enough narration. The alligators seen both in captivity and in the wild are not repugnant but gorgeous; in some shots, their eyes glow.

The ickiest thing to be seen in the film is a shot of a leech being pulled off producer Paling's leg. Otherwise, everything is marvelous and fascinating. You can't often say "amaze me" to your television set and expect it to comply. That is one reason the National Geographic Specials are so terrific. You expect them to amaze you, and they do.