15 
The Functions of a Local Natural BWistory 
Society, with special veference to the study 
of Plant Galls, 
By Puitip B. Mason, M.R.C.S., F.Z.S., F.L.S., &c. 
(Presidential Address delivered November 8¢h, 1889.) 
THINK that it may not be out of place to consider 
briefly the functions which a perfectly organised local 
Society should fulfil, the objects of its study, and the 
means by which these studies can best be carried out, 
and to do this, I must first rapidly run over the subjects included 
in the words Archzeology and Natural History. 
Of course the foremost place is occupied by Geology, for 
without the earth itself, there could be no Archzology or Natural 
History to investigate. This includes the character and succession 
of the strata in the neighbourhood, the conditions under which 
each bed has been formed, their paleontology, or the knowledge 
of the animals and plants which inhabited the land at each 
successive epoch, as far as their remains have been preserved 
in the rocks. Chemistry and Physics are also necessary to examine 
the constituents of the various formations, and show how the 
metamorphosis of the debvis coming from the primitive rocks into 
their existing forms has taken place ; while Meteorology enables us 
to understand how, during the long series of ages, the surface of the 
land has been carved into its present condition of hill and dale, and 
_ how the process is still being carried on at the present time by the 
