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unvaccinated and vaccinated persons, and, as I have already 
shown, it is now more fatal to adults than to children. It 
is evidently, therefore, gradually assuming the leading 
features of the dreaded plague ; and, as it is at the same 
time rapidly extending its ravages in spite ot vaccination, 
it becomes a matter of grave importance to ascertain the 
cause of the change in order that means may be devised to 
arrest its progress and counteract its effects. 
MICKOSCOPICAL AND NATUEAL HISTOEY SECTION. 
January 15 th, 1877. 
E. W. Binney, Esq., F.RS., F.G.S., Vice-President of the 
Section, in the Chair. 
“ On the Occurrence of Crataegus oxyacanthoides (Thuill.) 
in the neighbourhood of Manchester,” by Chakles Bailey, 
Esq. 
In a paper already published in the “Proceedings” of 
the Society, “ On the Hawthorns of the Manchester 
Flora,” I pointed out that three species of Cratcegus occurred 
in this neighbourhood. The most frequent of these is the 
CrcBtagus monogyna, Jacq., and it is easily recognised by 
the diverging veins of the leaf and by the single style. A 
second species, the G. Jcyrtostyla, Fingh., occurs in Botany 
Bay Wood, near Worsley ; but it has not, to my knowledge, 
