5 
Dr. SCHUSTEE, F.R.S., gave an account of his visit to 
Grenada in connection with the expedition for the observa- 
tion of the recent total eclipse of the sun. 
MICEOSCOPICAL AND NATUEAL HISTOEY SECTION. 
Ordinary Meeting, September 20th, 1886. 
Professor Williamson, F.R.S., President of the Section, 
in the Chair. 
Tlie Peesident gave an address, in which he explained 
very fully “ The present state of our knowledge of the Car- 
boniferous Calamitinse.” 
Mr. Daebishiee exhibited some specimens of Hydmctinia 
from Japan, and also a case of fragments of Pumice Stone 
which had been washed on shore in Mauritius, in Septem- 
ber, 1885, and were supposed to have been thrown into the 
sea by the eruption of Mount Krakatoa in August, 1884, 
and been drifted, in 13 monthvS, across the Indian Ocean, 
Floating banks of such stone have been reported by various 
navigators amongst notes on that eruption. The angles are 
removed and the sides smoothed. 
These stones carried upon them specimens, often crowded 
together, of Ostrea multiradiata and of a small Chama, a 
