194 vine: YORKSHIRE CARBONIFEROUS AND PERMIAN POLYZOA. 
least, Millepora gracilis, PliilL, was undoubtedly built up round a 
central rod. On this account "they re-christened the species 
Rhahdomeson. 
On the publication of my family name, which originally appeared 
without the sub-section B., Mr. E. 0. Ulrich readily adopted the 
name, but in his definition of the family he included Rhomhopora, 
Meek, and he further suggests that probably Anisotrypa, Ul., may 
ultimately be placed in the family. Following this suggestion, and 
wishing, for the sake of working Palaeontologists, to keep myself in 
accord with American workers, I subsequently adopted the sub- 
section B in my Yoredale Polyzoa, and in the Polyzoa of the Gayton 
Boring.* As both sections of the family are largely represented in 
the Yorkshire as in other British Carboniferous rocks, it may be as 
well to giA^e rather full notes on the Yorkshire species especially. 
Genus RiiABDOMESON, Young and Young. 
1874. Rhabdonieson, Y. and Y., Ann. Mag. Nat. Hist. Ser. 4, vol. 
xiii., p. 327. 
1875. „ „ Ibid, vol. xv., p. 334. 
1884-5. „ (Section A), Vine, Proc. Yorks. Geol. Soc, 
vol. ix., p. 23. 
Section A. 
Zoariiim slender, rod like. Axis a thin calcareous tube to which 
the Zocccia are attached, and from which they radiate in all directions. 
1. Rhabdomeson gracile, Young and Young. 
1841.? Millepora gracilis, Pbill., Pal. Foss., Cornwall, Devon, etc. 
1854.? Ceriopora gTacilis, Morris, Catalogue Brit. Fossils; Millepora 
gracilis ? McCoy, Carb. Foss., Ireland, p. 195. 
1874. Rhabdomeson gracile. Young and Y., Ann. Mag. Nat. Hist., 
vol. xiii., pi. XV., figs. 1-6. 
1875. „ ,, John Young, Trans. Eding. Geol. Soc, 
pp. 400-402. 
1880- 1. „ Vine, 1st Brit. Assoc. Rep. Foss. Poly. 
1881- 2. ,, ,, Vine, Proc. Yorks, Geol. and Polyt. 
Soc, vol. vii. 
♦ See 1885 and 1887 papers in Bibliography at the head of this section. 
