72 REPORT—1849, 
Without any knowledge of Dumortier’s discovery, Professor Allman had demon- 
strated some years ago the existence of this organ in Cristatella, and had also referred 
it to the nervous system, describing it as the great cesophageal ganglion of the Bryo- 
zoon. 
Professor Allman was now enabled to lay before the meeting some additional facts 
connected with this subject, as he had recently discovered filaments proceeding from 
the ganglion, so that the distribution of the nerves could now no longer be considered 
asa matter of doubt. The author described the great oesophageal ganglion in Pluma- 
tella repens as sending off a large filament to each of the tentaculiferous lobes, a smaller 
one passing off at each side to embrace the cesophagus, while a very short one ap- 
peared to proceed from the ganglion and dive into the substance of the cesophagus, 
where it could no longer be traced, and another set of filaments was observed to pass 
forwards and distribute themselves to the organs about the mouth. 
Among other points in the anatomy of the Bryoxoa, Professor Allman mentioned 
his detection of striz in the muscles, and the tendency of the muscular fibre to break 
itself into dises. The tube of the tentaculz was shown to be lined by a distinct mem- 
brane; the invaginated part of the internal tunic was proved to be composed of two 
portions distinct in structure, separated from one another by a sphincter, and a com- 
plete system of muscles was demonstrated in connexion with the oral valve. 
From the facts now laid before the meeting, Professor Allman maintained the ne- 
cessity of removing altogether the Bryoxoa from the position among the radiate 
classes in which they had been placed by authors, and raising them at once to the 
sub-kingdom of the Mollusca. 
On a New Freshwater Bryozoon. By Prof. Autman, M.D., M.R.I.A. 
The subject of this communication was discovered in the Commercial Docks on the 
Thames, during a late examination of that locality in company with Mr. Bowerbank. 
It possesses many points of resemblance with P/umatella repens, but differs essen- 
tially from this animal in the circumstance of each cell being separated from its 
neighbour by a distinct septum, as in Paludicella. 
On the Reproductive System of Cordylophora lacustris, Allm. 
By Prof. Autman, M.D., M.R.I.A. 
Certain branches of Cordylophora lacustris, instead of terminating in polypes, bear 
upon their extremities an oval vesicle, into which the contained matter of the stem is 
continued. These vesicles arefilled with spherical bodies, and must be viewed as the 
true ovarian receptacles of the zoophyte. 

On Lophopus crystallina, Dumortier. By Prof. Atuman, M.D., M.R.I.A. 
In this communication the author noticed the occurrence of Lophopus crystallina in 
the pond of the Dublin Zoological Gardens. This elegant zoophyte is the Polype a 
Panache of Trembley, and had been first characterized as a genus by Dumortier. It 
has since been confounded with other genera, and Dr. Johnston, in his excellent 
‘History of british Zoophytes,’ adduces Trembley’s Polype a Panache asasynonyme 
of Alcyonella stagnorum. An examination however of the present zoophyte must 
convince us of its true generic distinctness, and of the correctness of the views main- 
tained by M. Dumortier, and subsequently by M. Van Beneden, who has figured and 
described it in his memoir ‘ Sur Jes Polypes d’eau douce de Belgium.’ 
Mr. R. Ball exhibited a new dredge which he had recently constructed for natural” 
history purposes, being an improvement on the instrument called Ball’s dredge. 
Mr. R. Ball exhibited a drawing, and described the structure of a specimen of 
Bryarea scolopendra found in Dublin Bay by Dr. Corrigan. 


Notes on some Tubicole. By C. Srencz Bate. 
Yerebelia medusa.—The author remarked that while building, this annelide placed 
the material collected by its tentacular cirri upon its mouth, where it is, he presumes, 


