By ROBERT ABERNATHY Illustrated by WEISS All younger generations have been going to the dogs ... but this one was genuinely sunk! "Junior!" bellowed Pater. " Junior! " squeaked Mater, a quavering echo. "Strayed off again—the young idiot! If he's playing in the shallows, with this tide going out...." Pater let the sentence hang blackly. He leaned upslope as far as he could stretch, angrily scanning the shoreward reaches where light filtered more brightly down through the murky water, where the se