Pvn H,i I'UitlS

specimens of it at Uddevalla,
BRACHIOPODA. 6
in the course of a short
exploration of the raised sea-bed in that remarkably in-
teresting place. T. septata (or septigera), as regards the
frequency of its occurrence, may be placed
in the same
category. The examination of fossiliferous strata is
attended with no risk, and the specimens are procured
without much difficulty; but I much doubt if we should
not find in a modern sea-bed, of the same extent and
having similar conditions, a collection of Brachiopoda
fully equal in number and variety to those contained in
any one Palseozoic, Mesozoic, or Cainozoic formation.
So many recent species have been made out of solitary
or a very few specimens, that it is evident much remains
to be known of this curious group as it at present exists.
Being individually numerous, and comparatively low in
the scale of organization, the tendency to variation is
of course great. An examination of nearly all the types
of recent species induces me to suggest the necessity of
a complete revision of these so-called species.
This group has been for more than half a century a
favourite study of naturalists. Pallas, Cuvier, De Blainville,
Owen, Quenstedt, Deshayes, Yogt, Forbes, Hux-
ley, M. J. Muller, Schmidt, Deslongchamps, Carpenter,
Barrett, Woodward, Gratiolet, Hancock, F. Muller,
Macdonald, Lacaze-Duthiers,and Shaler have at different
periods
contributed a vast store of information as to the
structure of recent Brachiopoda; while De Koninck,
D'Orbigny, M'Coy, King, Davidson, Suess, and other
able palaeontologists have made us acquainted with the
fossil forms. Mr. Reeve has also rendered some good
service in respect of the synonymy and geographical dis-
tribution of existing species. Mr. Hancock's valuable
paper " on the Organization of the Brachiopoda " will
be found in the c
Philosophical
Transactions' for 1858.
b 2