In all the bony fishes previously mentioned the fin rays are soft and flexible, and in this respect they differ from those that are to follow, for the remaining families are all characterised by the presence of one or more sharp rigid spines on the dorsal fin, and often by similar spines on other fins. They constitute the group of Spiny-finned fishes. Of these we shall first take the prettily coloured Wrasses (family _Labridæ_), which live in the holes of rocks and under the cover of weeds on rugged coasts. These fishes are very voracious in habit, and the sea angler will find that they are ready to seize almost any bait that may be offered them, and even to attack almost everything that moves within sight; but they are likely to give much trouble since they will rush into the crevices of rocks or among large weeds when hooked, and thus frequently lead to the breaking of the line. Wrasses feed principally on molluscs and crustaceans, and are provided with extensile telescopic lips that enable them to pull the former from the rocks on which they creep, and the latter from their hiding-places among the rocks. They have also strong teeth in the gullet, by which they can crush the shells of their prey. There are several British species of Wrasses, one of which is shown in the accompanying illustration. The commoner ones are known to fishermen and juvenile anglers by quite a variety of local names. [Illustration: FIG. 236.--THE RAINBOW WRASS (_Labrus julis_)] The family _Gobioesocidæ_ contains some small and very prettily coloured fishes of very peculiar habits, known popularly as Sucker-fishes. They have one or two adhesive suckers between the pelvic fins by which they attach themselves to rocks, stones, and shells. Some are littoral species, and may be searched for at low tide; but others inhabit deeper water, and are seldom obtained without a dredge. [Illustration: FIG. 237.--THE CORNISH SUCKER] One of the former is the Cornish Sucker (_Lepadogaster cornubiensis_), which may sometimes be taken in a hand net by scraping the rocks and weeds at low tide on the south-west coast. It has two suckers, each circular in form, surrounded by a firm margin, within which is a soft retractile centre. This central portion is attached to muscles by which it can be withdrawn; and a vacuum is thus produced, so that the sucker adheres by atmospheric pressure. The structure of the sucking organs can be seen to perfection when the fish attaches itself to the side of a glass aquarium, and if it be taken in the hand it will cling quite firmly to the skin. This peculiar little fish is only about three inches long, and its broad head is marked with two conspicuous purple spots, with a blue dot in the centre, and surrounded by a yellowish ring.