6 Mr. F. M‘Coy on some new genera and species of 
shaped rims of growth, concave above and produced by the 
successive growths. from the centre leaving the promiment 
edges of the previous cells; weathered surface finely striated 
by the edges of the vertical lamellee, of which there are about 
twelve in a quarter of an inch : the horizontal oval section shows 
the centre to be excentric, close to one of the broad sides, and 
formed by the twisting of the radiating lamelle about an ima- 
ginary axis ; radiating lamelle very thin, of equal thickness, 
about 115 to 180 at the margin, some stopping and some 
uniting as they approach the centre, about which they are 
twisted in parcels; all the lamelle connected throughout, at 
regular intervals, by minute transverse vesicular plates: in- 
ternal structure exposed by horizontal and vertical sections, 
uniformly and minutely cellular. 
The great number and closeness of the lamellz distinguish 
this species from those published forms allied to it. | 
Rare in the lower carboniferous limestones of Arnside, Kendal, 
and Lisardrea, Boyle, co. Roscommon, Ireland. 
(Col. University of Cambridge.) 
Cyathaxonia costata (M‘Coy). 
Sp. Char. Elongate-conic, generally about one inch long and 
half an inch in diameter at the cup, which is circular and 
horizontal ; surface irregularly wrmkled transversely, and — 
marked longitudinally with remarkably thick, strong, sharply- 
defined striz, about seven in one-fourth of an inch; central 
solid axis very thick (often one line in diameter), and from it 
twenty-six thick, wedge-like, vertical lamelle radiate to the 
walls; transverse vesicular plates connecting the lamelle ex- 
ceedingly delicate ; in the sections the vertical lamellz are seen 
to dichotomise upwards, and the large curved plates of the 
loose vesicular structure incline upwards and inwards towards 
the axis. 
This is more slender in form than the C. mitratum (Schlot. sp.) 
or C. cornu-copie (Mich.), and from which and all the other tur- 
binated corals of the palzeozoic rocks it is distinguished externally 
by the strong, distinct, distant longitudinal ridges ; the internal 
characters approximate it only to the Cyathaxonia cornu (Mich.), 
from which it is distinguished by its simple, few and thick Ja- 
melle and thick axis, as well as more turbinate form. 
Rare in the carboniferous limestone of Derbyshire. 
(Col. University of Cambridge.) 
