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Show 544 REV. S. J. WHITMEE ON THE GENUS ANTENNARIUS. [Nov. 2, kindly determined the present individual, which I have sent to the British Museum, as A. coccineus (Less.). The fish is found sticking to corals and stones on the reefs of Upolu, and is very difficult to distinguish from the coral or stone. Its Samoan name is La'otali. As this fish was brought to m e alive, I kept it in an aquarium in m y study for a few days to observe its habits. It was brought in a cocoa-nut shell with very little water; and its stomach was greatly distended with air. W h e n put into the aquarium it was some minutes before it could sink. It struggled hard to get down, and as the air was discharged it went down, and immediately attached itself, in a vertical position, to a block of coral by means of its pectoral and ventral fins. These were distended, and looked very much as if they served the purpose of sucking-disks (like the united ventrals in some of the Gobiidee) as well as answering in place oi feet. When attached it held on very firmly, and I had a difficulty in disengaging it. Natives have told m e that they have taken up a block of coral with this fish attached, and have had great difficulty in shaking it off. After being in the water a few minutes m y fish moved from its first position and, apparently, sought one better adapted to its habits. It cut a poor figure when attempting to swim, and prepared to walk where it could. It again fixed itself, in a vertical position with the head up, in an indentation in a coral block which pretty well matched its size. W h e n attached it looked much like the block itself, the cutaneous tentacles and ocellated spots greatly resembling the fine seaweed and coloured nullipores with which the dead portions of corals and stones are more or less coated in these seas. As I * watched it I could not help thinking that this fish presents us with what we n o w call (since M r . Bates introduced the term) "mimicry." Being a slow swimmer and carnivorous, it has to get its food by stratagem. Hence the advantage of those characteristics which make it so grotesque in appearance-wide vertical mouth, rough and spotted skin with cutaneous tentacles, and the anterior dorsal spine modified into a soft tentacle. I had positive evidence that the example in questiou was carnivorous. A short time after it had been put into the aquarium it vomited a slightly decomposed fish 1 inch 5 lines in length. This was one of the small fishes always seen in great abundance about the coral patches, nibbling at the fine seaweeds and the growing points of the corals. The capture of such fishes when unconsciously approaching it would, I believe, be greatly facilitated by the strong current produced when this Antennarius sucks the water into its capacious jaws. From its vertical position when fixed on a stone, the jaws open horizontally ; and they are very wide. W h e n examining the fish I placed it in a basin with about a pint of water. So much water was drawn into its jaws and expelled with such force through the foramina, which are directed backwards behind the pectorals, that a rapid rotatory motion was produced in all the water. This, I imagine, would be sufficient to engulf many a small fish or crustacean within its stomach. |