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other substances, were collected from 2*495 litres of the air 
of this city* — a quantity which would be respired in about 
10 hours by a man of ordinary size when actively employed. 
I have to add that there was a marked absence of particles 
of carbon amongst the collected matter. 
MICROSCOPICAL AND NATURAL HISTORY SECTION. 
February 24th, 1868. 
J. B, Dancer, F.R.A.S., President of the Section, in the 
Chair. 
Mr. SiDEBOTHAM sent two beautifully finished water- 
colour drawings, accompanied by the following note : — - 
“ I send you a couple of drawings of the dry-rot fungus 
Merulius lachrymans, remarkably fine. Mr. Lynde, our 
Treasurer, brought me the specimens, which he had met 
with during the demolition of some old buildings. The 
drawings are of the natural size. It is very rarely that 
such perfect specimens are found, showing, as this one does, 
the curious structure of the species, and its connection with 
both the pore and the gill-bearing divisions of fungi.” 
Mr. Dancer exhibited some sand from the sea-shore at 
Santos, South America. This sand was remarkably silvery 
in appearance, a large portion of it consisting of minute 
plates of mica, and very transparent fragments of quartz, 
which made it an interesting object for the polariscope. It 
was rich also in Foraminifera, spines of Spatangus, and frag- 
ments of Coralline. 
* Behind Dr. R. Angus Smith’s laboratory. 
