266 BY THE DEEP SEA. 



slip through our fingers, or over our hands, several times, we 

 corner him at last, and transfer him to a large bottle in spite 

 of his slipperiness. He proves to be the Five-bearded 

 Rockling (Motella musteld), as we see at once by the four 

 barbs on the upper jaw and the solitary one beneath. These 

 are really sufficient for identification purposes, for no other of 

 our shore-haunting fishes is decorated in precisely the same 

 manner. However, we will briefly indicate the appearance of 

 the fish. The dorsal fin commences at about one-third of the 

 Reckling's length, reckoning from the front, and continues 

 close up to the tail. The anal fin starts a little beyond the 

 vent and continues near to the tail below. Pectorals rounded ; 

 ventral long and pointed. Just before the beginning of the 

 dorsal fin there is a long, narrow, and delicate membrane that 



THREE-BEARDED ROCKLING. 



looks like another dorsal fin, but is not. Of the barbs from 

 which the fish gets its distinctive name, two are directed 

 forwards and upwards, two forwards and outwards, whilst the 

 fifth goes forwards and downwards. 



The Three-bearded Rockling (Motella vulgaris) is very like 

 the last-named species, but has only one pair of barbs on the 

 upper jaw, and a single one on the lower. Mr. R. Quiller 

 Couch discovered that one or other of the Rocklings, probably 

 all three for there is another species, the Four-bearded 

 (Motella cimbria] build a kind of nest by jamming fragments 

 of coralline into a cranny, and depositing their eggs in the 

 mass as the work proceeds. 



From one nest-building fish to another is a very easy transition. 



