Potato Talk is Harold Courlander's ""Talk"" (from The Cow-tail Switch) moved from Africa to whimsyland and set to rhyme. The very funny story of the potato who upbraided the digging farmer, of the dog who told the farmer to do what the potato said, of the tree that refused to let the farmer hit the dog with its branch, etc., is no less if no more funny here. (Except that the chief refuted by his ceremonial stool was more of a mockery than the mayor undermined by his front porch chair.) But the pictures, clever as they are, do fetter the imagination by giving every gabby object a face. Potato Talk is a congeries of potato heads, nevertheless likely to speak to kids who'd never get to know the Courlander.