BLENNIUS, blenny, in natural history, a genus of fishes of the order Jugulares. The generic characters are, head sloping ; body lengthened, sub-compressed, lubri cons ; gill membrane six-rayed ; ventral fins two, three or four-rayed, unarmed ; anal fin distinct. There are two divi sions; viz. A. head crested ; B. head not crested ; and according to Gmelin there are 18 species, though Dr. Shaw enume rates more. B. galerita, or crested blen ny, inhabits the European ocean, is four or five inches long ; its body is brown and spotted ; the skin at the corner of the upper jaw loose, projecting ; dorsal fin extending from the head almost to the tail; ventral fin small ; vent under the ends of the pectoral fin. This fish is fre quently found about the rocky coasts of Great Britain. B. ocellaris has above the eyes a single ray, and on the first dorsal fin a large black ocellate spot. It inha bits the Mediterranean Sea ; is eight inches long ; the body is without scales, dirty green, with olive streaks, rarely pale blue : the flesh is eatable, but in no great estimation. Although Linnaeus and others have described this fish as having two dorsal fins, Block considers it as hav ing in reality but one ; the sinking in of the middle part being in some specimens much deeper than in others, seems to be the cause of this difference of opinion. B. saliens is a very small species, observ ed about the coasts .of some of the south ern islands, and particularly those of New Britain. It seems to be of a gregarious nature, and is seen swimming by hun dreds, and flying as it were over the sur face of the water, occasionally springing among the rocks. It is naturally formed for celerity in its movements, the pecto ral fins being very large in proportion to the body. They are nearly of a circular form when expanded, and when contract ed reach almost as far as the vent on each side. B. superciliosus has a small head, with large eyes, and silvery irides, and immediately over each eye is situated a small palmated crest, or appendage, di vided into three segments. The body is
covered with very small scales, and is of a yellow or gilded tinge, and marked with numerous and irregular spots of dusky red. The dorsal fin commences at the back part of the head, and is continued almost to the tail ; but near its commence ment suddenly sinks, so as almost to give the appearance of a smaller anterior dor sal fin, separate from the longer one the pectoral fins are of moderate size ; the ventral ones didactyle, and rather long ; the vent is situated in the middle of the abdomen, from which part the anal fin commences, and reaches as far as the tail. This species is found native in the Indian seas, grows to the length of about twelve inches, and is viviparous. There is, however, another species, denominat ed B. viviparus, which, like that just no ticed, is distinguished by a particularity that takes place in but very few fishes, except those of the cartilaginous tribe ; being viviparous, the ova hatching inter nally, and the young acquiring their per fect form before the time of birth. Not less than two, or even three, hundred of these have been sometimes observed in a single fish. It might he imagined that so great a number, confined in so small a space, might injure each other by the briskness of their motion ; but this is prevented by the curious disposition of fibres and cellules among which they are distributed, as well as by the fluid with which they are surrounded. When ad vanced far in its pregnancy, it is scarcely possible to touch the abdomen without causing the immediate exclusion of some of the young, which are instantly capable of swimming with great alertness. The B. viviparus is a littoral fish, and is found about the coasts of the Mediterranean, and the Baltic and Northern Seas, and sometimes it.enters the mouths of rivers. It feeds on the smaller fishes, &c. It is taken by the line and net; but is not es timated as food, as its bones acquire a greenish colour by boiling. See Plate II. Pisces, fig. 2