BLE'NNIUS, Blennies (French, Baveuses), a genus of Fishes of the section Acanthopterygii and family Gobioidce (Gobies). Both the Greek and the French names have been applied to this genus from the mucous matter with which the bodies of these fishes are covered. They may be easily distinguished by their having the ventral fin placed before the pectoral, and containing generally but two rays. The head is short and rounded ; teeth long and slender, and placed in a single row ; body long, compressed, smooth, and possessing only one dorsal fin, which extends nearly the whole length of the back ; they have no air-bladder.
The species of this genus are small, live in shoals, but not in great numbers. They are very active and tenacious of life, and frequent rocky coasts, where they may often be found in the pools of water left by the tide, hiding themselves among the weeds and in the crevices of the rocks.
The genus Blennius of Linnmus, in Cuvier's 'Regne Animal,' is divided into the following subgenera : Mysodes Salarias, Cirrhibarba, Maramoides, Opistoynathus, and Zoarcus. At present we confine ourselves to the Blennies, properly so called, of which, according to Mr. nurell, we have five species frequenting our coasts. The first, B. Montagui, Montagu's, or Diminutive, Blenuy, is generally of an olive-green above, spotted with pale-blue shaded to white ; belly white, pectoral fins spotted with orange. The head, viewed laterally, forms an obtuse angle in front, and is furnished with a transverse conic or angular fimbriated crest. The dorsal fin has 30 rays, pectoral 12, ventral 2, anal (which extends from the vent to the tail) 18, and the caudal (which is rounded) 14. It is found on the south coast of Devon.
B. ocellaris, the Ocellated Blenny, or Butterfly-Fish, is scarcely three inches long, the head is rounded, the part anterior to the eyes very short, and above the eyes two slender fimbriated appendages are situated ; body elongate ; dorsal fin extending from the back part of the head to the tail, and consists of 26 rays, of which the first is con siderably longer than the rest, the nine following diminish in length to the eleventh, which is shortest, the twelfth nearly double the length of the last, from this the remaining rays gradually increase in length to about half-way, and then decrease towards the tail ; a large dark brown spot extends from the sixth to the ninth ray. The pectoral fins have each 12 rays, ventral 2, anal 17, and caudal II. The body is of a pale-brown colour, varied with patches of a deeper hue ; the pectoral and ventral fins are darker than the others. This species frequents the coast of Devonshire and elsewhere, but is not common.
B. yalloruyine, the Gattorugiuous Blenny, is about five or six inches in length ; it is elongate, rather robust anteriorly, the forehead slopes considerably from the posterior part to the anterior; the head is grooved between the eyes, and furnished with two branched mem branes situated just above the eyelids; the dorsal fin extends from the beck part of the head to the tail, the central part is very slightly nar rower than the rest. The fins and body are of a dark reddish-brown
colour, the belly and hinder portion of the former is of a paler brown. The dorsal fin has 33 rays, the pectoral fins are broad and rounded, and have each 14, the ventral fin 2, and the anal 23 rays ; the tail is slightly rounded, OA has 11 rays. It has been found in Poole Harbour and other parts. Not common.
B. pholis, the Shauny. In this species all the rays of the dorsal fin are nearly of equal length, except the eleventh and twelfth (which are short) ; the number of these rays is 31, pectoral 13, ventral 2, anal 19, caudal 11 ; the colour is very variable, but consists of shades of brown.
B. phais may however be readily distinguished from any of the known British species by the absence of the appendages on the head.
B. Yarrellii, the Crested or Verse11'. Itlenny. This species may be known by its elongated even shape, the uniform length of the rays of the dorsal tin, the form of the tail (which has the external rays shortest, the others increasing in length to the middle, thus being somewhat lanceolate in shape), and the four appendages of the head which are all finibriated. Two of these appendages are placed one over each eye, and connected by a transverse fold of skin ; behind thew are placed the other pair, which are of a larger size. The fin rays are, dorsal 51, pectoral 14, ventral 3, anal 36, and caudal 16.
This species was formerly confounded with B. palmironius and B. galerita, but Valenciennes has pointed out its distinctive characters and named it after the distinguished British iethyologist whose name it now bears. A specimen of this very rare British fish was exhibited amongst the earliest specimens in the Aquavivarium in the Regent's Park, and is still alive (July, 1853). Many other species of Blenny have been exhibited in the tanks of the establishment. All the species are remarkable for the facility with which they use the ventral fins for enabling them to cling to and move about upon the rocks and stones by which they are surrounded.
BLE'I'llAlt IS, a genus of Acanthopterygious Fishes, which accenting to Cuvier belongs to the seventh family of that tribe, called Scomhe roida. They may be distinguished by their having long filaments to their second dorsal, and to their anal fin rays; ventrala much prolonged, the spines of the first hardly piercing the skin; body elevated, the profile with the ordinary degree of curvature.