ON THE SILURIAN SPECIES OF GLAUCONOMRE., 329 
23. The Strvnian Spectres of Grauconome, and a SueeEsteD Crasst- 
FICATION of the Patmozorc Potyzoa. By Grorce W. SHRUBSOLE, 
Esq., F.G.S., and Grorer R. Vine, Esq. (Read June 21, 1882.) 
| Abridged. | 
Tue genus Glauconome, originally founded by Goldfuss, was so modi- 
fied by Lonsdale, as to become virtually a new genus, of which 
Glauconome disticka from the Dudley Limestone is the type. Later 
on came the discovery by Sedgwick of apparently a similar polyzoan 
from the Bala beds of North Wales. This was regarded by Prof. 
McCoy * as identical with the Wenlock species, and, as such, has 
been generally received. 
We have been of late examining these Silurian species of Glau- 
conomé, both as to their identity with one another and their con- 
nexion with the Carboniferous and Devonian species, and we find 
that the Bala and Wenlock species are not even generically related, 
while the members of the lar ge Carboniferous group have not the 
~ least affinity with the type species from the Wenlock beds. 
The present Bala, Devonian, and Carboniferous species evidently 
belong to a modified group of the Cyclostomatous Polyzoa, while the 
type species from the Wenlock can only be classed in a distinct 
division of the Polyzoa, for which at present no provision is made. 
In coming to thts decision, we have been mainly guided by zoarial 
form, and not outward resemblance. Evidence in this direction has 
been carefully sought for in the several species. In Glauconome 
distwcha from the Wenlock Limestone we find the cell open and ex- 
posed throughout its entire length; this, we find, is not accidental, 
but characteristic. The cells are built up of a series of thick 
longitudinal walls running parallel with the branch, and divided at 
regular intervals by cross walls, which go to form the cell or, rather, 
cell-area, which may be pyriform or quadrangular in shape and 
depressed in the centre. The keel is normally rounded, having on 
the elevated portions prominent nodes. 
The remarkable feature about the cell is its open character ; for 
out of the many examples we have examined we have not found it 
otherwise. That this is not due to the wearing away of any part 
of the structure is apparent from the fact that even more delicate 
polyzoans associated with it are not so affected. Lonsdale noticed 
the same peculiarity ; for he says “that the nature of the covering 
and opening of the cells is unknown.” ‘This is still the extent of 
our knowledge. 
We turn now to the other species of Glauconome from the Bala 
beds, which McCoy regarded as identical with G. disticha. In 
working out the affinity of this species, we have been favoured with 
specimens from Glyn Ceiriog, North Wales, in which the cell-fea- 
tures are well shown. The zocecia are seen to be long and cylin- 
drical in shape, buried in the length of the branch, and the cell- 
neck bent, and protruded through the branch. 
* British Palzoz, Foss. p. 49. 
Q.J.G.8. No. 158. Z 
