Notes on Myriapoda. 27 
If such be the case, the protoluciferin may be of service to 
the animal as an efficient constituent of the complex fluid 
produced by the mingling of the secretions of the glands of 
the sternal and episternal regions. ‘This complex fluid may 
have one or a number of uses, and there is a multiplicity of 
possibilities to choose from. It may act as a cement for 
nest-building, as a lubricant, or as a protection from the 
attacks of micro-organisms living in the soil ; and here we 
may note that the films of excretion we examined critically 
contained remarkably few micro-organisms, and the sternite 
is evidently kept very clean in a healthy luminous G. car- 
pophagus. Or, again, the fluid may act asa directional guide, 
enabling the animal to retrace its steps by perception of a 
track of the excretion made on the outward journey. Or, to 
take a last example of the possibilities, it may, owing to its 
property of drying rapidly, be of service to the animal in 
helping to free the body from excessive surface-moisture 
in damp or wet weather. 
Summary. 
Briefly to summarise the most important results of cur 
enquiry: up to the present, we way say that in GroruiLus 
CARPOPHAGUS, protoluciferin, here essential for light-produc- 
tion, 1s secreted by the white glands which lie immediately 
dorsal to the sternal and episternal plates. Upon the 
application of stimuli to the central nervous system, mus- 
cular contraction takes place and the ‘protoluciferin glands 
discharge their contents to the exterior into contact with 
the excretions of other glands opening upon tle ventral 
surface. The fluid thus excreted is viscous, colourless, with 
an odour swt generis, acid in reaction, a and exhibiting the 
micro-staining properties of a bacteria-free acid protein. 
It contains within itself all the essentials for the chemical 
action which results in the production of light and the 
formation of crystals. 
Future work lies in the further elucidation of the chemical 
aud pliysical aspects of the subject, and in the search for the 
real explanation of the economic value of the phenomenon. 
Thanks. 
Mention has been made in the course of our paper to the 
help given to us by Professor Newbery and Mr. C. W. Ashton. 
We are also indebted to Mr. Henry. Stephen, M.Sc., Lee- 
turer in Chemistry in the Victoria Uniyersity of Manchester, 
