OF SOUTIIERX INDIA. 
3.3 
This species is closely allied to II. Simonyi, Reuss, from the Gosau deposits, 
but the latter has somewhat larger and more regularly rounded and elevated calyces. 
Locality. — Near Moravia toor, in a brownish earthy limestone ; apparently very 
rare. 
Formation. — Ootatoor group. 
XVI. Genus. — PLACASTREA, gen. nov., 1873. 
Corallum massive ; calyces irregularly disposed on the upper surface, closely 
connected with each other by a septo-costal murail; septa on their upper edge 
granular, laterally in their entire length equally and rather finely denticulate ; 
columella in its entire length consisting of a solid compressed lamina, with a finely 
granular upper edge, similar to that of the septa. 
This genus differs from true Aslrea by its entirely solid compresscdly columnar 
columella ; the septa are in both equally granular and equally denticulate, hut the 
denticles are in Flacastrea not enlarged at the inner ends of the septa. Externally 
in general appearance the genus has very much the character of an Isastrea. 
A single species occurs in the Ootatoor beds of South India, and I am not 
acquainted with any other which can he referred to the same genus. It appears to 
represent Cyphastrea in the group of true Astreid^, which have the calyces con- 
fluent, not isolated and provided with elevated margins. 
Placastrea elegaxs, Stoliezka. PI. VII, Fig. 1. 
Flacast. corallum irreyutariter expansum, modice crassum, stih-pedicellatum, 
versus maryinem tenue, stiprd undulate irregulariter convexiusculum ; calycihus 
plerumque suh-hexagonis, minorihus atque majorihus inteiposUis, 4 «c? 7 mm. latis, 
modice concavis, coslis brevissimis suh-ungulate elevatis junclis ; septis confertim 
gramdatis, in quatuor cyclis dispositis, eyclo quarto scepe imperfecta, Us ad primum 
atque secundum cyclum pertinenlihus usque ad columellam fere extensis, ccsleris 
conspicuiler crassiorihus ; columella compresse styliformi, 1 ad l o mm. tonga, modice 
exserta, margine superiore minute granulata. 
The only specimen examined is a fragment of a large, apparently planorhoid, 
and suh-pedicellate corallum ; its lower surface is much weathered off, so that the 
probable existence of an epithcca cannot he ascertained ; the upper surface is irre- 
gularly but slightly convex. The calyces arc of rather large size and are moderately 
excavated, separated by elevated sub-angular ridges, which are crossed by the 
eostm. There is no regularity to he observed in the arrangement of the ealyces, 
and smaller and larger ones are intermixed. The larger calyces generally have 
four complete cycles of septa, but in tlie majority of them tlie fourth cycle is in- 
complete ; all are finely and rather densely granular on the upper edges, and finely 
denticulated on the sides. 
Locality. — Odium, in brown limestone. 
Formation. — Ootatoor group. 
I 
C 105 ) 
