196 vine: YORKSHIRE CARBONIFEROUS AND PERMIAN POLYZOA. 
could not find any trace of the fossils I was in search of Indeed, 
judging from Mr. Hall's paper, and lists of fossils, I now doubt 
whether he ever saw the Millepora gracilis, Pliill. Not to be baffled, 
however, I wrote to Mr. Newton again, asking him if he could tell 
me where PhiUips' types were, but he writes me (Sept. 23, 1889), " I 
am unable to say where Phillips' type of Millepora (Ceriopora) gracilis 
may be, but I liave nuide a rough tracing of the figure, and copied word 
for word the description given." So far good,but not wholly satisfactory. 
Genus Millejyora. Millepora gracilis. Character : slender, 
cylindrical ; surface covered by oval or sub-rhomboidal cells, the 
terminations of tubes passing obliquely from the axis. Intercellular 
spaces granular (or porous no branched specimens have been seen. 
It is closely allied to 3Iillepora rhombifera, Phillips' Geology of York- 
shire, vol, ii , pi. i., f. 35. 
Locality in Xorth Devon : Croyde, Brnshford, Pilton. Phill. 
Palaeozoic Fossils, p.p. 20, 21, pi. xi., figs. 31(/, 31^. 
The brief description of Millepora rhomhijera is as follows : — 
" Branches cylindrical, with acute rhomboidal cells in (quincunx." 
Geology of Yorkshire, vol. ii., pi. i., f. 35, p. 199. 
If any of my readers possess an example of the Pilton Millepora 
I should be glad to examine it. 
Rhabdomeson rhombiferum (Pliilhps' sp. ? pi. vii., fig. 5). 
1836. Millepora rhombifera, Phill. Geol. Yorkshire, p. 199. 
1854. Ceriopora „ Morris' Catal. Brit. Fossils. 
1875. Rhabdomeson rhombiferum, Young and Young, Ann. Mag. 
Nat. Hist., Ser. 4, vol. xxi., pp.' 333-336, pi. ix. ^ee 
Nomenclature and references as under R. gracile. 
Zoarium stem-like, slender, cylindrical, free. Branches of nearly 
equal diameter, given off at wide intervals and at right angles to the 
stem. Zomia in quincunx all round the stem. Vestibules rhomboidal 
or hexagonal in outline and bounded by tuberculated ridges ; area of 
vestibules larger on one face than on the other, and slanting inwards 
towards a narrow opening, the true orifice of the Zooecia. Tubercles, 
large at the angles of junction, average number of tubercles round 
each area about sixteen. Central axis slender and slightly flexuous. 
Gonocysts oval, compressed or elongated. 
