192 THE ZOOLOGIST. 
kept the Finsen rays in operation from 10.45 p.m. to 1.30 a.m., 
but, owing to unsuitability of the conditions for handling 
batteries and generating hydrogen, the current was rather inter- 
mittent. The only insects which came to the Finsen ray cone 
were a few small Diptera. This experiment ought certainly to 
be tried again, and should under favourable conditions succeed 
in attracting the male Glowworms, since the spectral analyses of 
Finsen rays and Glowworm light are similar. 
In the course of experiments made during June 238rd—29th, 
both in the dark-room and out-of-doors, I found that red was the 
most attractive colour to male Glowworms; the fluorescein 
sereen and diffuse white light were the next; quinine solution- 
screen, blue and green, were ignored ; bright white light at 
close quarters was evidently disliked, and markedly avoided. In 
the field I set up a long strip of canvas on posts; behind this 
were placed a number of small stands to support the bicycle- 
lamps or other sources of light. Within four yards of this 
canvas screen were seven female Glowworms, five of which 
remained unmated, after all others which I had located were 
mated. Several dozen males came close past these females on 
their way to my red light; the only obvious difference in the 
conditions surrounding these females being the presence of my 
experimental lights. 
In 1910 the larve were late, not appearing on the road until 
the first week in May ; females began to shine about May 20th ; 
by June 16th I had located sixteen, and a few males had 
appeared. After this I saw practically nothing more of them ; 
possibly a heavy thunderstorm on the evening of June 20th, 
when 1°18 in. of rain fell in about two hours, may have accounted 
for this. In 1911 they were very scarce. This year a number 
of larve are already about (April 20th). 
In conclusion, the three interesting points are—(1) that 
female Glowworms often take up and occupy a permanent 
position; (2) that male Glowworms may appear in flights of 
at least several hundreds; (8) that male Glowworms, like most 
insects, show a marked preference for red light, which is curious 
in this particular case, seeing that the light of the female, 
which should be specially attractive, is at the other end of the 
spectrum. 
