178 THE JOURNAL OF BOTANY 
of certain organs. It Sho Ga even begun to — an etio- 
ot so fo : 
pammen ee © as hinges the nature of the material diay are called 
upon to examine, for the majority of the remains found—and they 
the internal structure has been rved, it 1s only — capable 
of being investigated in thin sections insignificant in area. 
The whole of the organs or parts of a species are very seldom 
all preserved together at the same time and foun d at the same 
palzobotany, of which we speaking, work been much 
slower. Pal ~ipr espa are not called upon to exercise their 
i na so oi “2 palzobotanists ; and is only 
ies on and veil ata the work of a er of a century or 
more) has more recently still been utilized to the best advant- 
e only through the rapid advance of m technique and 
ern 
improvements in the making and the mode of examination of 
sections, as well as by the collateral progress made in ers 
of the microscope. This material has, moreover, best herpes 
mainly from the lower part of the Coal Measures, 
sion ma tween iaabetaeg thickening in pt: and gymno- 
sperms in the case of Calamodendron, Sigillaria, &e. 
Indeed, — plant work has been absolutely ——— cree or 
less to the Coa rassi 
that is to em the floras of the fri Ordovician, ‘Silen 
Devonian, Old Red Someemeey om Triassic, Liaasie, and very tinasie 
I may say here that I am at present engaged upon a study of the Carbo- 
sth Flora of the Midland Coalfields, a pete I have ote _pursuing some 
years, and in which I am now aided by a grant from the British Association. 
One of its op aioe - fa obtain some clues as to gr past colgin a the types of 
plants then domi 
t+ Pion sar wo in ‘this direction has been done by Mr. H. Smedley, who has 
already seman vetesr & most masher He series of models in wax of the paleozoic 
seed-plants and other important groups 
