MARKINGS OF FISH. 383 



that an example of this Trumpeter exhibited in addition to 

 the normal longitudinal stripes a very distinct series of broad 

 transverse bands of a dark grey hue. These transverse 

 bands, some five or six in number, seemed to underlie the 

 ordinary longitudinal series. On examining a number of 

 specimens they were all found to exhibit the same peculiarity, 

 and which fact demonstrated that the phenomenon was per- 

 fectly normal. Furthermore, all the Silver Trumpeters, 

 Latris forsteri, the typical living daylight tints of which are 

 a pearl-grey ground with golden or reddish-brown longi- 

 tudinal stripes, were found to be decorated with similar 

 supplementary transverse bands of a dark grey hue. 



The most remarkable incident, however, associated with 

 the phenomenon now brought under notice has yet to be 

 related. It so happened that one of the smaller specimens 

 of the Real Trumpeter, Latris hecateia, confined in a small 

 shallow tank, was one night seized and mutilated by a cat in 

 such a manner that the sight of both of its eyes were de- 

 stroyed. While losing its eyesight its more essential vital 

 functions were in no way impaired, and recovering from its 

 wounds it floated quietly, though blindly, about its tank and 

 took food, as previously, freely from the hand. With, how- 

 ever, the enforced interruption of the action of actinic light 

 upon its optic nerves the fish assumed and permanently 

 maintained that colour modification previously exhibited only 

 at night. It would thus seem that the action of actinic light 

 upon the optic nerves has a very distinct influence upon the 

 appearance or suppression of the deeper seated colour bands 

 now under consideration. The microscopic pigment cells of 

 which these colour bands are ultimately composed become 

 apparently contracted through the access of daylight to the 

 optic nerves to such an extent as to be invisible to the 

 ordinary vision. It was observed by me later on that these 

 latent transverse colour bands became also temporarily 

 visible under conditions of extreme nervous tension, and 

 especially during the death throes of the fish when removed 

 from their native element. 



The next and more widespread occurrence of colour bands 

 in fish to which I would direct attention is more permanent in 

 character, and for the most part associated with young or 

 immature individuals. In this connection it may be remarked 

 that the Trumpeters that were the subjects of the foregoing 

 observations were relatively young, representing that half- 

 jnatured gregarious condition when they are popularly 



