New Genera of Fossil Corals. 399 
ity, poriferous on all sides. Pores oval or subangular, arranged 
between longitudinal elevated lines.—Species H. fragilis. 
opening upward and outwards from the base. Near Fenestella in 
general aspect.—Sp., P. explanata, P. constellata, P. ensiformis. 
Genus Rurnopora, Hall, p. 48.—[Bryozéoid?] Corallum con- 
sisting of an expanded calcareous crust, either subcylindrical and 
hollow or explanate, poriferous on the two sides; cells arranged 
somewhat in quincunx order, roundish or oval, and strongly 
raised in little papilla: or pustules above the surface —Species R. 
verrucosa, R. tubulosa. : 
2. Niagara Group. 
Genus Potypiiasma, Hall, p. 112.—Corallum turbinate [Cy- 
athophylloid]; lamelle numerous, thin, apparently rising in pairs 
one often much stronger than the other; cell broad, margin 
thick and strong, with a deep central pit; half the lamellae reach- 
ing to the centre of the cell, where they are complicated or con- 
torted ; transverse septa below the central part of the cup obso- 
_ lete or irregular. Allied to Calophyllum, but does not show the 
transverse septa characteristic of that genus.—Sp., P. turbinatum. 
Genus Conornyiium, Hall, p. 114.—Corallnm turbinate or 
subeylindrical, having transverse septa in the form of inverted 
cones set one within the other; rays or lamelle very thin, nu- 
merous and denticulate. In weathered specimens the transverse 
the centre ; cell deeply concave in the centre and separated from 
the outer portion by a distinct rim, both the nner and outer por- 
Near the Diphy- 
ble in size ; rays twelve or more, 
and ascending points; transverse’ septa direct. 
id more especially, Favistella, but with spiniform rays ins 
