PROCEEDINGS OF SCIENTIFIC SOCIETIES. 229 
intuitive impulse to emit their light at certain intervals as a protective 
influence, which intervals became assimilated to each other by imitative 
emulation. But whatever the inciting causes of the phenomenon, he 
affirmed that the fact itself was incontestable, and a frequent subject of 
remark by all observers there. 
Mr. Jenner Weir said that he had noticed that when a glow-worm was 
captured, the light began gradually to diminish in intensity, but did not 
quite cease to be visible. 
Mr. Meldola remarked that when in Ceylon, in 1875, he had captured 
numerous specimens of a Lampyrid (Luciola vespertina, Fab. = Calophotia 
perplexa, Walker), which was swarming everywhere over bushes and tall 
grass. ‘The flight of the species was straight, and the insects did not fly in 
gregarious swarms. When captured and put in a box it gradually diminished 
the intensity of its light in the manner described by Mr. Weir, but if left 
undisturbed, was soon glowing with full brilliancy. Mr. Meldola observed, 
in conclusion, that the exact nature of the phosphorescence was still an 
unsolved problem, interesting both to the physicist and biologist. Some 
years ago he had examined the spectrum of the glow-worm, and found that 
it was continuous, being rich in blue and green rays, and comparatively poor 
in red and yellow. 
Mr. Pascoe also exhibited the two sexes of Isopoyon hottentottus, a 
Dipterous insect, which he was informed by Mr. R. W. Meade, of Bradford, 
had been hitherto unrecorded in this country. Above a dozen were 
seen gamboling in the air in a confined spdce among some yew trees at 
Box Hill, occasionally settling on the leaves. When he had taken four or 
five specimens the remainder, probably alarmed, disappeared. He remarked 
that the members of the family to which this fly belongs (Asilid@) are 
generally solitary in their habits, alighting on the ground in some pathway 
or open spot, then darting off a short distance. They are perhaps the most 
daring and ferocious of all insects; they have even been known to pounce 
upon and carry off a tiger-beetle (Cicindela). 
The Secretary exhibited, on behalf of Mr. George Francis, of Adelaide, 
specimens of a South Australian moth (dnapea, sp.?}), which feeds on the 
native Hucalypti. (See Proc. Ent. Soc. 1879, p. xv). 
Mr. Meldola read the following note “On the Protective Attitude of the 
Caterpillar of the Lobster Moth” :— 
““Most entomologists have admitted that the grotesque attitude of 
those caterpillars forming Newman's ‘ Cuspidate’ group was in some way 
protective, but it is only quite recently that Dr. Hermann Miller has 
made known (‘ Kosmos,’ Noy. 1879, p. 123) the results of his observations 
on the caterpillar of Stawropus Fagi, which observations now for the first 
time tend to show the true meaning of this attitude in the species in question. 
When sitting on a twig in its natural position the head and first five segments 
