Oops, sorry, that typo should be read as "chalk-white" (though I suppose caulk can be white, too!). In case I didn't make it clear, the only difference between the two races of aliens in "Let That Be Your Last Battlefield" was that one race was white-on-the-right and the other race was white-on-the-left. The intentional irony was that, when the two men were shown in profile arguing face-to-face, their faces appeared to be of the same color!