76 
VINE : NOTES ON YOEEDALE POLYZOA. 
2. Fenestella tuberculo-CARINATA, Etlieridge, Jan. 
— Fenestella sp. Eth. Jun., explanation of sheet 23, Memoirs of 
Geol. Survey, Scotland, p. 101. 
= Fenestella arctica, Salter, var. Scotica^ Eth. Jun. Ann. Mag., Nat. 
Hist, Vol XX., p. 31, July, 1877. 
= tuberculo-carinata, Vine, Proceed. York. Geol. Soc, 
Vol. VII., p. 335. 
= ,, tuberculo-carinata, Young". Trans. Geol. Soc, Glasgow, 
May, 1882, pp. 182-188. 
Zoarlum forming large . and small expansions of unknown 
dimensions, but over four inches in diameter, even iu its imperfect 
condition. Interstices (branches) carinated, and occasionally bifurcat- 
ing, with large zooecial aperture at each angle of bifurcation. 
Dissepiments, short, alternate, normally thin, but thickening according 
to age. Fenestrules either hexagon gal or quadrangular; measured 
over large surfaces where the characters are pretty constant, the 
number of fenestrules to six lines, are in length sixteen, in the 
breadth about twenty three. Carina (keel) zigzag, faintly conspicuous, 
or well rounded, bearing on the surface from three to five blunt or 
finely tapering spines to each fenestrule. Zooicia large, orifice large 
with well-developed peristome, three cells — generally a constant 
character — on either side of the fenestrule, the middle one occasionally 
indenting the margin. Reverse granular or finely tuberculated, with 
a prominent — slight or well rounded — tubercle at each corner of the 
quadrangular, or slight]}^ hexagonal fenesti'ule. Spiniferous processes, 
very robust. 
Locality and Horizon: Yoredale; Ilolker Park, Little Urswicli. 
This species — though not abundant in the Yoredale shales of 
either Yorkshire or Lancashire — has all the characters of the best 
preserved of the Scotch specimens. The spiniferous process — either 
attached or broken off — have special features, and for the size of the 
species are very robust, and the hook -like prolongations are always 
turned towards the Zoarium. As none of the authors referred to in 
the above synonyms, have drawn up full descriptions of this well 
marked type, I have availed mj^self of remarks made, by Mr. John 
Young, and by Mr. Robert Etheridge in the details furnished. 
