Ho ro, the rattlin' bog, and the bog down in the valley-O Rare bog, and a rattlin' bog, and the bog down in the valley-O In that bog there was a hole, rare hole and a rattlin' hole And the hole in the bog, and the bog down in the valley-O And in that hole there was a tree, rare tree and a rattlin' tree And the tree in the hole, and the hole in the bog And the bog down in the valley-O And on that tree there was a bough, rare bough and a rattlin' bough And the bough on the tree, and the tree in the hole, and the hole in the bog And the bog down in the valley-O And on that bough there was a limb, rare limb and a rattlin' limb Limb on the bough and the bough on the tree, and the tree in the hole And the hole in the bog, and the bog down in the valley-O ...and so on... adding: BRANCH, TWIG, LEAF, NEST, BIRD, EGG YOLK, CHICK, WING, FEATHER, FLEA, EYE, SPECK, GERM AMOEBA, PARAMECIUM, VIRUS and SUB-ATOMIC PARTICLE