642 THE OCEAN WORLD. 
form two discs. In the Lump-fish, Cycopterus lumpus (Fig. 402), 
the disc formed by the ventrals forms a sort of sucker, by which the 
fish attaches itself to the rocks ; while the genus Achineis is remark- 
able for having on its head a disc-like sucker, which according to 
M. Blainville is an anterior dorsal fin strangely metamorphosed. 
Fig. 402z.—The Lump-fish (Cyclopterus lumpus). 
The Zchineis remora is an inhabitant of the Mediterranean, and 
abounds in the Indian and Atlantic Oceans. It is furnished with a 
flat disc, which covers its head, as represented in Fig. 403, which is 
formed of a number of transverse and movable cartilaginous plates. 
Aided by this organ, it attaches itself firmly to rocks, and even to 
ships and larger fishes, such as the Dog-fish (Acanthius), which it 
meets with in its wanderings. Its adhesion to those objects is so 
strong that the strength of a man fails to separate them. It invari- 
