PROCEEDINGS OF SCIENTIFIC SOCIETIES. 231 
able to strike backwards and a little upwards. In some forms with very 
long tails, such as Lychas, &c., it might be quite possible for the animal to 
insert its “ sting” into the soft parts between the segments; but he thought 
it was questionable whether, in this mild way, any poisonous matter would 
be ejected. Another difficulty was that when the tail was so bent back 
the convexity of the sting would be downwards, and consequently its point 
would be upwards and away from the cephalothorax. 
Mr. S. Stevens exhibited, on behalf of Mr. Pim (who was present as a 
visitor), a dwarfed female specimen of Plebeius Icarus (Lycena Alexis). 
The Rev. A. E. Eaton exhibited three plates of drawings of Hphemerida, 
showing the structural details of the species represented. 
The Secretary exhibited, on behalf of Mr. George Francis, of Adelaide, 
the microscopical specimens referred to at the last meeting, which had 
been kindly mounted for exhibition by Mr. William Cole. 
Mr. Howard Vaughan exhibited a series of Cidaria russata from York- 
shire and the Isle of Arran, showing the local variation of this species. 
The Rev. H. S. Gorham read a paper on the Lampyride, in continuation 
of those communicated at the meetings of December and February last, the 
present instalment concluding his revision of the genus Photinus. 
Mr. Gorham also read a paper summing up the results of his observations 
on the Lampyrida, with respect to their phosphorescence, which he believed 
to serve the part of a beacon for attracting the sexes to one another. In 
support of this conclusion he stated that he had found that the eyes of 
these species were developed in magnitude according to the amount of 
luminosity displayed. With regard to the typical species of the family, he 
had observed that in the most highly organized genera, such as Lamprocera 
and Cladodes, the light-emitting faculty did not appear to be developed in 
proportion with the rest of the organs, and that the eyes were also reduced 
“in a direct ratio with the light,” being small and uniform in both sexes, 
whilst the antennz were ‘‘ developed in inverse ratio as the phosphorescence 
is diminished.” In illustration of this supposed correlation between the 
development of the antennz and the intensity of the light, Mr. Gorham 
exhibited a selection of species arranged in three groups. 
Mr. Pascoe thought it was much to be regretted that Mr. Gorham 
had not been able to observe the phosphorescence of some of the exotic 
Lampyride in their native haunts, as he had no doubt that many of the 
opinions now advanced would thus have to be considerably modified. 
Sir Sidney Saunders observed that the discussion involved two distinct 
questions,—namely, the flashing at intervals and the simultaneous action of 
large numbers in displaying their luminosity,—both of which he considered 
as indisputable facts. As regards the first, he mentioned the circumstance 
that when flying past, free from all obstructions, the Lwciola suddenly 
emits its light, and then remains untraceable until it repeats its flash at a 
