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56
G. E. VINE ON THE WEDLOCK POITZOA.
It is only after very careful study that I introduce to the paleon-
tologist, as a palaeozoic type, this remarkable genus. Haime, in his
' Jurassic Bryozoa,' vindicates his use of the word JSpiropora in place
of the many synonyms which have been introduced into scientific
literature since the time of Lamouroux. There are two very distinct
4, 5, & 6.
-Spiropora regularis, Vine.
5
4. Shows the general habit and mode of branching, and character of unworn
cells: X 12. 5. Cells worn, showing the internal cast of the tubular cell

X 24. 6. Outline cells of a worn specimen, showing arrangement in
spirals: X 24.
features in the genus

and these, as defined by Jules Haime, may be
briefly noted: — 1. The Zoarium is dendroid . with forked branches

cells elongated and closely connected. This feature is apparent in
the Palaeozoic type. 2. " The peristomes are circular and more or
less projecting, and they form at the surface of the branches circles
which usually are not closed, but each constitutes one of the turns of
a spire so many times interrupted. These rings are the more regular
the more distant they from each other. "When they are very close
they are often difficult to recognize "

• .

This feature is also present in
the Palaeozoic type. Haime, however, speaks of his species as being
perforated " with very small and round pores." This feature is not
present in this early type; indeed perforated pores are very rare in
Palaeozoic Polyzoa. I have seen them in some Carboniferous species
of Fenestella f

but even in these they are of rare occurrence unless
specimens are specially prepared to show them. In his Eocene
Bryozoa Prof. Eeuss % figures and describes three species of Spiro-
pora

— S. tenuissima, Eeuss, having somewhat the general character
of Entalopliora

S. pulchella, Eeuss

and S. conferta, Eeuss. The
Silurian species more closely resembles S. pulchella than the other
two species of Eeuss, both in the character and in the ordinary
arrangement of the cells. It must not, however, be taken as evidence,
satisfactorily settled, that the Palaeozoic type blends naturally with
the Oolitic and Tertiary types. This is not so. The evidence is

Haime's ' Jurassic Bryozoa,' Genus viii. pp. 193, 194.
t In F. plebeia, M'Coy. In Alecto frondosa, James, the punctured pores are
a marked feature. % ' Tertiary Bryozoa of the