Blennies have soft, shiny, scaleless skins.
The Sand-smelts are small carnivorous species inhabiting the seas of temperate and tropical regions. Many enter fresh-water, and some have become entirely acclimatised there. Some species bear a very close resemblance to the true smelt, from which, however, they may be readily distinguished by their small, spinous, first back-fin. The young of at least one small group or genus of this family are remarkable for their habit of clinging together for some time after they are hatched in dense masses and almost incredible numbers.
The Grey Mullets are brackish-water fishes, feeding on vegetable growths and minute shell-fish. They also suck up large quantities of sand into the mouth for the sake of the minute organisms contained therein; much of this is passed on into the stomach, which is thick and muscular, like that of many birds. Altogether some seventy species of grey mullets are known, the majority of which attain a weight of about 4 lbs., but there are many which grow to 10 or 12 lbs. All are eaten, and some highly esteemed.
The Flute-mouths, Sticklebacks, and Tortoise-fishes are three closely allied and extremely interesting families. The first are really gigantic marine sticklebacks, in which the jaws are produced into a long tube. They are shore-fishes, entering brackish water, and confined to sub-tropical and tropical parts of the Atlantic and Indo-Pacific.
Photo by W. Saville-Kent, F.Z.S.] [Milford-on-Sea.
NORTHERN MULLET.
A member of the family of Grey Mullets.
Photo by Reinhold Thiele & Co.] [Chancery Lane, W.C.