204 REPORT—1883. 
embedded in Limestone, which Mr. Nickles has also sent me. This 
appears to be the species which Mr. Ulrich renames R. Nicholsoni, Ulrich. 
Under present circumstances I can only catalogue the following British 
Species :— 
Wenlock Shales Ptilodictya Lonsdalei, Vine. 
s Limestone ne lanceolata, Lonsdale. 
Mr. J. M. Nickles has also pointed out to me that the species which I 
have called P. interporosa, Vine (Wenlock Polyzoa, ‘Quart. J. G. Soc.’ p.67), 
is not a Ptilodictya at all, but that it closely resembles Stictoporella 
flexuosa, James. It certainly very closely resembles the delicate species 
of James, but it differs considerably from Mr. Ulrich’s 8S. interstructa. I 
‘shall therefore adopt the generic, and retain my own specific name. 
Wenlock Shales. Stictoporella interporosa, Vine (=Ptilodictya 
[interporosa). 
” ” ” 8p. 
There still remains P. scalpellum (Eschara), Lonsdale, which for the 
present must remain in abeyance. This also is not a Ptilodictya. 
ARCANOPORA, Vine. 
= Sulcoretopora, D’Orb. (pars) of authors. 
Type Flustra ? parallela, Phill. ‘Geo. of Yorkshire.’ 
Zoarium ? 
of the zoariwm. 
Sulcoretepora was founded by D’Orbigny in 1847, and since then a 
variety of species of very different characters have been included in the 
genus. Professor Morris, in his ‘ Catalogue of Brit. Fossils,’ places the 
genus in his family Reteporida, a Cheilostomatous type, and it is un- 
certain how authors regard the character of the species placed in it. 
In the ‘Catalogue,’ Professor Morris includes the Flustra parallela of 
Phill., and the Vineularia raricosta, M‘Coy. As the definition given by 
D’Orbigny is evidently inapplicable to these species—‘ Cells in series in 
furrows on one side of simple depressed branches ’—the name ought to 
be dropped. At present I can only direct attention to the species already 
named, to which the Messrs. Young have added another—/Sulcoretepora 
Robertsoni, Y.and Y. I have not yet completed my investigations, but I 
have sufficient evidence to induce me to include the first two species in 
the present group. 
Zoecia arranged in parallel lines on opposite sides 
Guauconome, Goldfuss, restricted. 
‘Stem stony, thin, elongated oval, branched, cells disposed longi- 
tudinally, and alternately in rows over one half the surface, the other half 
striated longitudinally. Nature of the covering and opening of the cells 
anknown. Silurian System, pl. XV. fig. 12, and ¢ (p. 675). 
The above is Lonsdale’s description of this restricted genus, and as 
the type of Goldfuss and Lonsdale is the same species—G. disticha, 
Goldf.—it seems to me desirable that both the genus and species should 
be limited to the type, unless the earlier Bala species can be included in 
the same genus. It is very evident that the structural characters of the 
‘Carboniferous species that have heretofore been included in the genus are 
