114 



hook and line, on which it has been caught, cannot be used 

 with success to catch other fish. It was, therefore of special 

 interest to note its habits in captivity. Only one fish was 

 observed to attack it — a KHp-fish, which snapped once and 

 only once at its protruding tail. 



Sometimes during the day, if a piece of fish flesh was placed 

 before the head of the fish, its method of feeding might be 

 observed. It occasionally drew the food into the hole, but 

 often consumed it without scarcely moving it from the place on 

 which it lay, a fact which ma}^ explain the mysterious disappear- 

 ance of bait on a hook without any indication to the fisherman 

 of a " bite." 



It is well known that when the fish is irritated or startled 

 it gives off large quantities of a mucus-like substance con- 

 sisting of very fine long threads, which normally lie coiled up 

 in the skin of the fish. This was readily observed, though the 

 only occasion on which it was seen to do so naturally, was 

 when it accidentally touched the tentacles of a sea anemone 

 with its projecting feelers. 



The secretion of this mucus would thus seem to be a method 

 of defence, but there is reason to believe that it may serve 

 another purpose. On examining the tank in the morning, 

 pieces of the mucus were often seen on the rockwork or on 

 small stones. Some of these might have been occasioned by 

 the irritation of contact with an anemone as above noted, bu^ 

 many pieces were found, where this could not ha\-e been 

 possible, for instance, on the branches of a large " red coral " 

 {Gorgonia flammea), which was suspended in the tank, and 

 among the branches of which the mucus sometimes appeared 

 like the web of a spider. When examined microscopically, it 

 was found that many minute forms of animal life had become 

 entangled in the coils of its innumerable threads. These were 

 chiefly small Crustacea, Protozoa, etc., and several Trematodes 

 were observed securely caught by a loop of the fine thread 

 round their sucker. Once or twice some of the fishes (Klip-fish 

 and Dasjes) were seen endeavouring to tear up this mass, and 

 though they dragged it about a little, it seemed to cause great 

 inconvenience by adhering to their teeth so that they had some 

 difficulty in shaking it off. In no case were they observed to 

 devour it. The only animals that were seen to eat this no 

 doubt nutricious mass were the Anemones and occasionally 

 one of these animals was obser\'ed with its gullet widely pro- 

 truded and closely applied to one end of the substance, which 

 was gradually drawn into the Anemone's stomach. 



Many of the pieces were, however, in such a position that they 

 could not be secured bv the Anemones, and these invariably 



