16 Dr. & the Rev. S. Graham Brade-Birks— 
to gauge the fall of intensity more exactly. With further 
refinements much greater accuracy might be attained by 
such a method. 
Stimulation. 
In the case of G. carpophagus we have found that the 
fullowing stimulations will cause the production of light :— 
(i.) Handling. 
(i1.) Pressure. 
(ili.) Sudden immersion in water. 
(iv.) Electric current from an induction-coil. 
Most of these foregoing stimulations were seen in deter- 
mining other points. Probably special experiments would 
reveal many other ways of stimulating the production of 
light by these animals. 
(v.) Eaposure in a glass tube to coal-gas passing through 
the tube. 
In this case the centipede was only momentarily luminous. 
(vi.) Attack by ants. 
Here a centipede which did not appear to be luminous 
when handled became so when ants were placed with it in 
the same tube. 
(vii.) On meeting another individual. 
Two centipedes, neither of which exhibited any luminosity 
on handling separately, were placed one by one in the same 
tube. Upon the introduction of the latter specimen there 
was a luminous display arising from one or both individuals. 
Reference has already been made in our thirteenth 
paper (2) to the methods of stimulating luminosity in Kent 
centipedes by local workers. 
(vili.) By crushing after death. 
It is convenient to add here that on one occasion when a 
part of the body of an individual, recently killed, was 
crushed in the dark phosphorescence was produced. The 
centipede had been killed in alcohol and the alimentary 
canal had been removed subsequently before the experiment. 
