224 CLASSIFICATION OF FISHES. 



mouth placed beneath, presenting, when closed, the ap- 

 pearance of a fissure placed longitudinally, and not, as 

 in all other fishes, transversely with the body : the eyes 

 are very small : the rays of the fins are obsolete, or 

 nearly wanting ; and there are no ventrals or pectorals. 

 Between Petromyzon on one side of Ampjhioxus, and 

 Myxene on the other, there are still wanting two types 

 to complete the circle of this family : one of these types 

 would also fill up the only link wanting between Amphi- 

 oxus and Leptocephahis ; while the other would connect 

 Amphioxus with Liparis and the lump-suckers. 



(198.) The Cyclopteridce, or lump-suckers, form the 

 concluding family of this order. Like the last, their 

 skeleton is so soft, that some of these fishes are said to 

 dissolve after death into nothing but jelly, or mucilage: 

 like the lampreys, also, they are adherent, or suckers ; 

 but this faculty, instead of lying in their mouth, is 

 transferred to the pectoral and ventral fins, both of 

 which, by being united into a circular disk (Jig. 44.), 



form two power- 

 ful suckers, by 

 which these ani- 

 mals adhere to 

 rocks, stones, or 

 other substances, and even to the hand of those who 

 capture them. They are smooth, destitute of scales, 

 and of an ugly appearance. Sometimes the disk, as 

 in the genera Liparis and Cyclopterus, is only single; 

 but in Lepadogaster* and Rupisuga, it is double. 

 Like all the fissirostral types, or their represent- 

 atives, the head of these fishes is uncommonly large 

 and greatly depressed, although the body is compressed : 

 the snout is rather lengthened and obtuse ; so that, in 

 short, we are presented with such a miniature resem- 



* The genus Piecephalus of Ra6nesque appears to differ from this, in 

 having the ventral or abdominal fins forming a semicircular plate, whose 

 concavity is turned towards the head, and furnished with scattered cup- 

 shaped suckers [sparse di cupule succhianti) ; there is no operculum, but 

 a three-raved membrane ; and the tail is heart-shaped, or emarginate. — 

 Raf.Cara.tt. p. 69. 



