92 VINE : BRITISH PALEOZOIC CTENOSTOMATOUS POLYZOA. 
elliptical, and joined together at their contracted ends. . . . Cell 
mouths not clearly determined, but appear to be situated near the 
middle of the cell," and the author further says " the genus is 
related to Hippothoa, but in the form and arrangement of the cells 
they differ widely." 
I have already described or referred to species found in the 
Wenlock shales, and some of the forms have been figured (Yorksh. 
Geol. and Polyt, Soc, vol. ix., pi. 12, figs. 11-12) as Rhopalonaria 
botellus, Vine, but I am unable to place any of the forms definitely 
in the Ctenostomatous group, neither am I able to add much more 
to the information that I have already given respecting these peculiar 
fossils. Mr. Ulrich places Rhopalonaria amongst the Ctenostomata, 
and in all probability he will be able, ere long, to illustrate and 
describe American forms, which are similar in some respects to our 
own. 
Lower Silurian, Cincinnati. 
Rhopalonaria venosa, Ulrich. 
1879. Jour. Cincin. Soc. Nat. Hist., vol. ii., pi. 7, figs. 24-24b. 
Examples of the British species which I have used for the 
descriptions in the present paper, will be placed in the British 
Museum (Nat. Hist.), and in the Museum of Practical Geology, for 
reference, &c. 
Explanation of Plates. 
Plate III. 
Figs. 1-4. Vinella repens, Ulrich. 
Shewing the different characters of the British Wenlock Shale 
examples. 
Figs. 5-7. Vinella repens, var. contorta, Vine. 
As the forms of this variety differ from the American V. repens, 
I have given the British examples a varietal name. 
Figs. 8-15. Ascodictyon filiforme, Vine. 
It appears to me to be impossible to break up the variations of 
this species for the purpose of placing them under distinct names. 
