Hans Gadow, The Cambridge natural history, Vol… (1909)
“ The colour is saturated green, the eyes are transformed into round, projecting shiny black beads, and the head is erect. The ludicrously dreamy, complacent look has given way to wide-awake alertness. They take all kinds of living food. When they find an earthworm, they first look at it, bending the head sharply down, lift themselves upon the fore-limbs and then pounce upon it, nipping the prey with the jaws, and then poking it down deliberately with the hands. ”
