 In some accounts, the dogs on the shore act differently according to their colour, yellow dogs would carry the soul of the deceased across the river, while white dogs refuse because they have just washed themselves and black dogs refuse because either they have just swum the river or because they are dirty.In Aztec folklore, the "ahuizotl" was a dog-like water monster with a hand on the end of its coiled tail.It was said to dwell underwater near river banks and would drag the unwary to a watery death.