Behavior of Cray Snapper i^'hen I'cd Conspicuous Fisiics. 301 



surface water. Several times it was seized by the snappers and again re- 

 leased. It could not be seen whether it again inflated itself, but it was 

 finally lost to sight seaward and probably escaped. 



(3) An individual 3 inches long was thrown outside the dock. The 

 snappers followed it for 5 or 6 rods, swimming below it and watching it, 

 but did not seize it. When it had gone out over the dark vegetation-covered 

 bottom, I followed in a row boat. It was swimming at the surface, making 

 with the pectorals a little eddy visible at a considerable distance. It moved 

 so slowly that a 16-foot dinghy could be brought to it by paddling stern fore- 

 most with a single oar. Nevertheless I had difficulty in capturing it in a 

 small tin can, because, when approached, it changed its course and dodged 

 about. It was finally captured and thrown from the dock on the shore side. 

 It was already inflated. The short tail, projecting like the neck of a jug 

 from the spherical body, was seemingly the only part of the fish that could 

 be seized. After a moment's hesitation the fish was taken by the tail by an 

 unusually large snapper. He took it to the bottom and mauled it back and 

 forth there as though to force it into his mouth or burst it. He finally lost 

 his hold on it and a second fish seized it by the tail. It passed then to a 

 third and a fourth and each in turn mauled it on the bottom. The fourth fish 

 finally forced it into his mouth and it disappeared. 



(4) An individual a little less than 3 inches long was thrown dead from 

 the dock and was at once taken. It was carried 5 or 6 rods down the 

 shore, apparently dropped, and then picked up by another fish. A careful 

 search failed to find it, and it was recorded as finally taken. 



Cliyloinyctcrus is an occasional visitor in this region and does not occur 

 normally on the reefs, but is often found in the open water in consider- 

 able numbers. It is conspicuous in open water. On account of its relative 

 unfamiliarity it appeared to oft'er a new problem to most of the snappers, 

 a problem involving erratic movement, together with inflation of a heavily- 

 spined body. The problem was nevertheless speedily solved. In the case 

 of No. 3 a single large snapper, possibly with previous experience of Chylo- 

 mycterus. led in the solution ; the others quickly followed. Conspicuousness 

 was here a disadvantage. 



{d) Ahudefduf marginatiis. This very conspicuous fish is often found 

 with the snappers when full grown. Its yellow and black bands suggest a 

 hornet (see plate i, figs, i and 2). It is deep-bodied, but its dorsal and anal 

 spines are relatively weak (cf. Chwtodon). It swims slowly, but is very 

 agile, as shown by the following experiences : Two young individuals, 0.5 

 inch and 1.5 inches long, were placed in a cylindrical aquarium 7.5 inches 

 in diameter and could then be captured only with great difficulty by the use 

 of a conical net with a 4-inch opening. Two young Liitianus griscns about 

 1.66 inches long could be readily picked up from the same aquarium with 

 the same net. It is exceedingly difficult to capture Adudefduf with a net 

 3 feet in diameter in open water. It usually escapes over the rim. Eleven 

 individuals were thrown from the dock to the snappers, 4 of these being 

 alive and active. The results were as follows : 



( 1 ) Very active, was taken at once. 



(2) Went about 15 feet pursued by snappers, but finally reached one of 

 the live-bo.xes and was left unmolested. 



(3) Was pursued by snappers which came within 8 or 10 inches of it. 

 It swam to a spile underneath the dock and was left unmolested. 



(4) Swam to the live-box without being pursued. 



