Roach.
Jimmy looked up from his paper just as Frank pulled in a good sized roach, and said,—
"Do either of you know how the chameleon changes its colour?"
Upon receiving an answer in the negative he read as follows from the paper in his hand:—
"M. Paul Bert has laid before the French Academy a résumé of the observations of himself and others on the colour-changes of the chameleon. They appear to be due to change of place of certain coloured corpuscles. When they bury themselves under the skin, they form an opaque background to the cerulescent layer, and when they distribute themselves in superficial ramifications, they either leave the skin to show its yellow hue, or give it green and black tints. The movements of the colour corpuscles are directed by two orders of nerves, one causing their descending, and the other their ascending, motions. In a state of extreme excitation the corpuscles hide below the skin, and do so in sleep, anæsthesia, or death. The nerves which cause the corpuscles to go under the skin have the greatest analogy to vaso-constrictor nerves. They follow the mixed nerves of the limbs, and the great sympathetic of the neck, and do not cross in the spinal marrow. The nerves which bring the corpuscles upwards resemble in like manner the vaso-dilator nerves. Luminous rays belonging to the blue-violet part of the spectrum act directly on the contractile matter of the corpuscles, and cause them to move towards the surface of the skin."
Chameleon.
"Now, can you tell me the plain English of that?"
"Read it again, Jimmy," said Frank.