When alarmed, it hurries across the surface of the water in a series of leaps.

It may be considered amphibious, as it lives as much out of the water as in it, and its most busy time is during low water.

Then it appears on the sand or mud, near the little pools left by the retiring tide; it raises itself on its pectoral fins into something of a standing attitude, and with its large projecting eyes keeps a sharp look-out for the light-coloured fly, on which it feeds.

Should the fly alight at too great a distance for even a second leap, the blenny moves slowly towards it like a cat to its prey, or like a jumping spider; and, as soon as it gets within two or three inches of the insect, by a sudden spring contrives to pop its underset mouth directly over the unlucky victim.

He is, moreover, a pugnacious little fellow; and rather prolonged fights may be observed between him and his brethren.