300 Papers from the Marine Biological Laboratory at Tortugas. 



well-known and formidable lancet at the base of the tail (plate 3, fig. 5; 

 plate 5, fig. 10). These are all weapons which the fish habitually use. 

 There is no evidence that the color of any of the species afforded them the 

 least protection against the snappers. These fish, with the exception of 

 Caranx, Chyloniycterus. and Leptechineis, are reef-fish. The snappers 

 which frequent the inner reefs are familiar with them; they are familiar 

 with the snappers. That their colors or patterns have no warning signifi- 

 cance for the snappers is shown by the following facts : 



(a) The snappers took them at once. They showed no trace of the hesi- 

 tation or refusal shown, after experience, toward tentacled red atherinas. 



{b) The fish attempted to escape, sometimes toward the shore, some- 

 times toward some other near shelter, such as is afforded by the spiles of the 

 dock or by the floating live-boxes beneath it. In this respect their be- 

 havior contrasts with that of many typical, warningly-colored animals {e. g., 

 the skunk and " Belt's frog," Belt, 1874), which do not flee from their ene- 

 mies, but depend for protection on their color. 



The fish which escaped were either speedy and not conspicuous, or were 

 hindered rather than helped by their conspicuousness. The following details 

 of these escapes illustrate this : 



(a) Caranx crysos is silvery and yellow, and not conspicuous when seen 

 on the yellow-white sand. One individual, 2.5 inches long, was released 2 

 or 3 feet from shore. It was pursued by snappers and fled along shore as 

 near as possible to the water's edge. It was several times captured with a 

 net and again released near the snappers, but each time it behaved in the same 

 way and finally escaped by following the shore. A second individual, thrown 

 from shore to a distance of 6 or 8 feet, was at once taken. 



(&) Chcetodon ocellattis (plate 3, fig. 5). — An individual 5 inches long 

 was thrown from the dock after the snappers had been brought together by 

 feeding them several atherinas. It was at once viciously attacked by a large 

 number of snappers together, and was lost to sight for an instant. As the 

 snappers separated, the Chcctodon was seen apparently uninjured and with 

 its spines fully erected. It immediately started seaward and was not further 

 molested. An individual 1.75 inches long, of a rather less conspicuous spe- 

 cies (C. capistratus, plate 3, fig. 6), was at once taken. The C. ocellatus, 4 

 inches long, was about 4 inches deep from tip of longest dorsal spines to tip 

 of longest anal spine. Such a fish is clearly protected by its size and arma- 

 ture, but not by its coloration, while a smaller individual of a closely related 

 species (C. capistratus), conspicuous and provided with means of defense, 

 is readily taken. 



(c) Chylomyctcrus schcrpfi. — (i) A specimen 3 inches long was thrown 

 from the dock. It swam vigorously seaward at the surface, followed by a 

 dozen snappers, which swam about below, approaching and receding. It was 

 finally lost to sight and not taken. 



(2) An individual about 5 inches long was thrown. It swam toward 

 shore and was picked up and thrown farther seaward. The snappers col- 

 lected beneath it and it inflated itself at sight of them, so far as could be 

 seen without being touched by them. It then deflated itself and swam more 

 rapidly so near the surface that the movements of its pectorals disturbed the 



