THE BUTTER-FISH. 



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The BUTTER-FISH, SWORDICK, or SPOTTED GUNNEL (Centronbtus gunellus], belongs 

 to this family, and is evidently one of the transitional species between the true blennies 

 and those which are placed at the end of the family. 



This fish is frequently captured upon our coasts, especially on the rocky shores, and is 

 mostly found hidden under stones and seaweeds in the rock-pools left by the receding 

 tide. The name of Butter-fish is very appropriate, and is given to it on account of the 

 plentiful mucous secretion which is poured over its body, and which renders it so slip- 

 pery that it can with difficulty be retained in the hand. It is quick and agile in its move- 

 ments, and even if confined within the limits of the rocky pool, is not easily captured. 



EYED BLENNY.-B/enfl/us ocellarls. 



VIVIPAROUS BLENNY. Zoarces vlvlparus. 



SEA WOLF.-Aaarrhichas lupus. 



The body of this fish is much elongated and somewhat eel-shaped, the head is small, 

 the muzzle blunt, and the dorsal fin is low and long, extending the whole length of the 

 back. The ventral fins are very small. The color of the Swordick is brown, in some 

 specimens with a purple and in others with a golden wash. Along the base of the dorsal 

 fin, and in some individuals upon the fin itself, are a number of bold black spots each 

 with a white streak on either side. A dark brown stripe is also drawn from the eye to 

 the lower jaw. The length of the Butter-fish is about six inches. 



