36 Mr. R. Etheridge on Carhoniferous Polyzoa. 



Localities and Horizon. Carboniferous shale, Hopeshield 

 Burn, near Mount Farin, Northumberland, probably near the 

 horizon of the Scar Limestone ; shale above the no. 1 or 2 

 limestone, Lower Carboniferous Limestone group, Harelaw 

 Quarrj, near Longniddrj Station, Haddingtonshire. 



Cotlectors. Mr, Hugh Miller, F.G.S., and Mr. James 

 Bennie. 



Genus Thamniscus, King, 1849. 

 (Annals Nat. Hist. 1849, iii. p. 389). 



Thamniscus pustulata^ B. Eth.,jun. 



Polypora ? jmstulata, R. Etheridge, jun., Mem. Geol. Survey Scotland, 



Expl. 23, 1873, p. 102. 

 Tliamniscus JRankini, Young and Young, Annals Nat. Hist. 1875, 



XV. p. 335, pi. 9 bis. 



Obs. In 1874 I described, in the explanation to sheet 23 of 

 the one-inch Geological-Survey Map of Scotland, certain 

 fragments of Carboniferous Polyzoa which I believed to be 

 new, with the remark " if it be a new species of Polypora, I 

 would propose for it the specific designation of'P.pustulata.^^ 

 I also pointed out that the disposition of the cells and mode of 

 branching were exceedingly like those seen in the type species 

 of Thamniscus, T. duhius, Schl., and suggested that it might 

 be a species of this genus. 



Since my notice of the fossil appeared, the Messrs. Young 

 have obtained a comparatively perfect example, and have 

 shown that it should be more properly referred to Thamniscus, 

 as I surmised ; but at the same time these authors have altered 

 the name to T. Rankini — quite an unnecessary proceeding ; 

 for I gave a perfectly intelligible description, and my specific 

 name is to all intents and purposes a good one. 



Genus Rhombopoea, Meek. 



Rhomhopora, Meek, 1872, Hayden's Final Report of the U.S. Geol. 

 Survey of Nebraska, p. 141. 



I would draw the attention of British palaeontologists to the 

 above genus of the late Mr. Meek, referred by him to the 

 "Polypi" (Actinozoa), but which will, \ think, probably 

 prove to be a Polyzoon. The genus was established for small 

 ramose corals with " non-septate, short, tubular cells radiating 

 obliquely outward and upward on all sides from an imaginary 

 axis ; cell-mouths rhombic or rhombic oval, and very irregu- 

 larly arranged in longitudinal and oblique spiral rows, the former 



