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Sigillaria, and there are no traces of striae upon their sides. 
The same may be said of somewhat similar lunette- shaped 
masses appearing on the outside of the internal radiating 
cylinder. 
The areol® on the walls of the cellules are more numerous 
than in any species of Pinites or Dadoxylon which have 
hitherto come under my notice, the P. medullaris of Witham 
having the walls of its elongated cellules reticulated with 
two, three, and four series of contiguous areolae, and those 
only on the walls parallel to the medullary rays, while in 
my specimen they are reticulated with six, seven, and eight, 
and not only on such walls, but also on the walls at right 
angles to the medullary rays. The lunette-shaped bundles 
of cellules both in the inside and outside of the internal 
radiating cylinder are different from those seen by me in any 
other specimens of Dadoxylon. For the purpose of distin- 
guishing it the name D. Oldhamium has been given to it. 
A paper was read “ On Air from off the Atlantic, and from 
some London Law Courts,” by R. Angus Smith, Ph.D., 
F.R.S., &c., President. 
The specimens of air collected by Mr. Fryer when on his 
way to West Indies, and those collected in Antigua, are 
worth remarking, as the first agrees with the figures obtained 
previously when examining air on the sea shore and open 
heaths of Scotland, where the highest average was obtained, 
and the second agrees with the numbers obtained in more 
inhabited but not closely inhabited places. 
Those from a law court are interesting ; they are the most 
deficient in oxygen of any specimens found by me during the 
day in inhabited places above ground. The first is almost 
exactly the same as the average found in the currents of 
galleries in metaliferous mines ; that from the lantern is 
nearly the same as the specimens found close to the shafts of 
the same mines, meaning of course the average of many 
