Notes on Myriapoda. 13 
luminous centipedes (see also Pl. I. fig. 6 and explanation 
of same). This book gives a very useful summary of many 
interesting points relating to the subject. All who have a 
comprehensive interest in the problems of the production 
of light by animals will find in the papers of a modern 
writer, Prof. Dahlgren (4), very valuable summaries of many 
of the results of a long line of observers. Prof. Dahlgren 
touches upon luminosity in the plant-world, and surveys its 
production in many of the systematic subdivisions of the 
avuimal kingdom. But from a consideration of that section 
of Prof. Dahlgren’s third paper (4c), which deals with the 
power of lighting in the animals with which our present 
study is especially concerned, we realise at once how much the 
problems met with here have baffled earlier investigators. 
II. Our recent INVESTIGATIONS. 
Introduction. 
On the 22nd of April, 1919, we were walking together on 
hills near our own home in Darwen, Lancashire, when we 
casually collected several Geophilidzaliveand took them home. 
They proved to be Geophilus carpophagus, Leach (fig. 1), and 
were luminous when stimulated in the dark. With this 
discovery a new era begins for us in our study of luminous 
centipedes. We had already experimented with some Jumi- 
nous specimens sent to us alive by members of the Dartford 
Naturalists’ Field Club, and had learned from their hints 
and our own experience that it was possible to keep these 
animals alive in jars if a good supply of fresh damp soil be 
provided for them; moreover, the power to luminesce is 
retained in captivity over a long period. But with a wealth 
of material at our doors we were able to carry on our 
research with much greater confidence. 
In Norfolk, during a holiday in May and June, 1919, we 
obtained one specimen of G. carpophagus between the trunk 
and bark of felled timber in Mr. Witton’s wood-yard, 
Heacham. This was luminous upon stimulation. The 
Misses Cox of Heacham and Mr. Witton were familiar with 
the occurrence of luminous centipedes locally, where they 
seem to be known as “ glow-worms.” 
Subsequently, at a joint field-meeting of the Lancashire 
and Cheshire Fauna Committee and the Burnley Natural 
History Society on 26 July, 1919, Mr. W. G. Clutten, one 
of the Vice-Presidents of the latter organization, took one 
specimen of G. carpophagus at Extwistle, near Burnley, and 
