12 
CRETACEOUS CORALS OR ANTIIOZOA 
iipon which Leptocijathus, Discotrochus, and otlier genera arc based. Tlierc have 
for the present only two species been described under tlie genus FI. Terqiiemi and 
FI. Orhignyi, both from the cretaceous rocks of Erancc. A third species has 
occurred in the Ootatoor (Cenomanien) deposits of the Triebinopoly district of 
Southern India. 
Platycyatiius indicus, Stoliczka. PI. I, Eig. 20. 
Flahjc. corallum conoideo sub-discoideum, hasi angastatum, medio paulo excuva- 
tiim, theca murali temdssima mh-lcevigata instructum I cultjce lato, modice e.vcavato, 
septis elevatis in (piinque cgclis perfectis dispositis, extus omninis fere ccqiialiter 
incrassatis., dense sed minute gramdatis, lateraUter costulis interruptls, dwari- 
catis et spimdis interpositis instnictis, sejotis qrrimariis et seciindariis fere cequalihus, 
crassissimis, tertiariis paido temdoribus, eccteris tenuissimis ; j}alis 21 elongatis, in- 
ceqnaUbns, tenuibiis ; colmnella circiter quartam partem latitudinis calyeis cequante, 
in superfioie gramdosa. 
This species has in general aspect a considerable resemblence to FI. Terqiiemi, 
but is readily distinguished from it by the presence of five complete cycles of septa, 
these being arranged in six systems. The form of the corallum is generally dis- 
coid, somewhat roundly angular at the periphery and narrowed at the base, on 
which alone the mural theca is developed ; this last ajjpears to have been nearly 
smooth. Round the periphery the septa are almost throughout equally thickened 
and finely granulated, but in the moderately concave calyx those of the fourth and 
fifth cycle are very much thinner than those of the three former cycles ; all are 
densely spinulose and costulate laterally. The ])ali appear to be only 2i< in niimber, 
placed opj)Osite the septa of the fourth cycle, and are unequal. In some cases there 
appear to be also short pali present opposite the tertials, but they are not well 
traceable in the only specimen examined. The columella is rather coarsely granu- 
lar and very slightly convex. 
Ijocality . — Xorth by cast of Odium, in a greenish-grey, slightly calcareous sand- 
stone, a single specimen occurred. 
Formation . — Ootatoor group. 
Family,— TR O CIIOSMII.ID.F. 
(As restricted by Fromentel.) 
The coralla are simple, generally sessile by a broad or narrow base, sometimes 
covered with an epitheca, but generally costatc on the surface; calyx round or 
ovate, concave; septa lamellar, entire on the upper edge, connected by numerous 
dissepiments, often forming a well develoj)cd coenenchyma. 
( ) 
