92 
VINE: NOTES ON YOKED ALE POLYZOA. 
25. Rhabdomeson gkacile (Phill. sp. Palasozoic Foss.) pi. X., 
fig. 11. 
== Millepora graciles, Phill. 
= Ceriopora gracilis, Morris's Catalog-ue of Brit. Foss. 
Bhahdomeson gracile, Young' & Young, " Annals," May, 1884, 
p. 337, pi. XVI., figs. 1 to 5. 
Rhabdomeson gracile Vine, Proc. Yorks. Geol. Soc, op. cit. 
Zoarium rod-like, slender, cylindrical and branching. Brandies 
coming off at right angles to the stem and never less than an inch 
apart, Stem consisting of a hollow axis formed by a thin calcareous 
tube, and of a series of cells ranged i-ound the axis. Zocccial 
apertures oval, surrounded by tuberculated ridges, which bear two 
blunt spines, one on the upper and the other on the lower angles of 
each aperture. Zocccia conical, consisting of two parts, the vestibule 
and the cell proper. 
Localities'. Yoredale ; Holker Park, Gleaston Castle, Little 
Urswick. Hurst, Yorks. Northumberland, and very generally 
distributed in British Carboniferous Rocks; Devonian (Phih). 
26. Rhabdomeson ehombifekum, Phillips, sp. 
= Ceriopora rhombifera, Phill. 
Rhabdomeson rhombiferuni, Y. & Y., Ann. Mag. Nat. Ilist., May, 
1875, pp. 333, 334, pi. IX. 
Zoarium slender, cyclindrical free. Branches of nearly equal 
diameter, given off at intervals at right angles to the stem. Zoacia 
opening all round the stem, orifice of zooecial chamber at the bottom 
of depressed area (vestibule). Vestibule rhomboidal or hexagonal in 
outline, bounded by narrow tuberculated ridges, the tubercles on 
which are larger at the angles of junction ; average number of 
tubercles round each area, sixteen ; areas of zooecial chambers 
more numerous on one side than on the other. " Plere and there 
depressed pits with quadrangular boundaries intervene between 
adjacent cell areas ; but the}' are cascal, and do not show in tranverse 
sections." Axis slender, slig'itly flexous. 
Localites : Yoredale ; Gleaston Castle, Holker Park, North 
Lancas., Hurst, W. Yorks. 
