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very choice diatoms, mounted hy Miller, and which were from a 
collection of Méller’s, from Baker’s, Holborn ; he had brought down 
for distribution a number of specimens of cyclostoma elegans and 
clausilia nigricans ; a couple of packets of loam, one taken from above 
and the other below the Wealden building stone, and sent to Mr. 
Onions by Mr. Grantham, who wished some of the microscopists to 
examine it for vegetable substance. 
That afternoon he had received a letter from Mr. Gwatkin and a 
bottle of water containing living creatures, taken from the supply 
cistern of the kitchen boiler of Mr C. Buckwell’s house. It appeared 
that, ‘‘since an alteration in the connecting pipe of the boiler and 
supply cistern, by which the temperature in the latter was reduced to 
luke warm, these creatures from time to time made their appearance. 
The cistern was of cast-iron, with tightly-fitting metal top. At first a 
little fine dust was seen on the surface, and, in a day or two after, the 
creatures themselves appeared.” 
Before coming down he had examined some and found they were 
a species of Thysanuride (spring-tails), He should fancy they were 
conveyed into the supply cistern from without. They belonged to a 
species which lived on the top of water. He did not consider they 
came from the Company’s supply, but from the house itself, All the 
Thysanuride delighted in damp places and fed on decaying vegetable 
substances, If the members present would look at one under the 
microscope, they would see the peculiar spring under the tail, whence 
their name, 
One evening of the previous week, while examining ‘‘ battledore” 
scales, to see whether he could confirm Dr. Anthony’s idea of the mark- 
ings being elevations on the ribs, he fortunately got some scales to stand 
on end, when he was able to see the papille standing out clear from 
the ribs). He had made a cork model of what he had seen, and 
was satisfied Dr. Anthony was right in the main ; but scales taken 
from fresh-killed specimens should be examined, as, in drying, they 
had a tendency to become flattened. 
Mr. F. E. Sawyer exhibited a block of indurated Portland stone, 
which was found by a mason in cutting a stone step, and pronounced 
by him to be flint. He showed it to Mr, Wonfor, who considered it only 
Portland stone altered possibly by igneous action, With a lens its oolitic 
nature could be easily made out, At Mr. Wonfor’s suggestion he had 
