Basilisk (the βασιλίσκος of the Greeks, and Tsepha (cockatrice) of the Hebrews), a name given by the ancients to a horrid monster of their own imagination, to which they attributed the most malignant powers and an equally fiendish appearance. The term is now applied, owing to a certain fanciful resemblance, to a genus of lizards belonging to the family Iguanidae, the species of which are characterized by the presence, in the males, of an erectile crest on the head, and a still higher, likewise erectile crest - beset with scales - on the back, and another on the long tail. Basiliscus americanus reaches the length of one yard; its colour is green and brown, with dark crossbars, while the crest is reddish. This beautiful, strictly herbivorous creature is rather common amidst the luxuriant vegetation on the banks of rivers and streams of the Atlantic hot lands of Mexico and Guatemala. The lizards lie upon the branches of trees overhanging the water, into which they plunge at the slightest alarm. Then they propel themselves by rapid strokes of the hind limbs, beating the water in a semi-erect position and letting the long rudder-like tail drag behind.

They are universally known as pasa-rios, i.e. ferrymen.