COELENTERA — CORALS. 
5.5 
Durham; GyathoplwiUum, largely represented in the Table- ^llery X. 
case, and lyy some polished slabs of C. rcrjmm- from Bristol ; waU-caBe 
ClisiopliyUuvfi and Aspidophyllum, whicli end the series. 
Henceforwai’d these Tetracoralla disappear from the rocks ; 
but the living Astraeid coral, Moselcya, has ^vhen young .a • 
four-rayed symmetry which suggests relationship to the 
Cyathophyllidae. It is possible that the latter forms were 
the ancestors of the Astraeidae. 
Xeither Permian nor Triassic corals are represented 
iu the British series, but there are shown specimens irom the Wall-case 
Zechstein, as well as the Klipstein collection from the Triassic 
beds of St. Cassian in the Tyrol. 
The next coral fauna represented in the British islands is 
that of the Lias, the earliest of the Jurassic corals. This Table-case 
Fig. 24. — J^oautharian Corals of Bajocian Age, from the Inferior Oolite of 
England, a, " Latomxanclrxa" Flemingi. b, Montlivaltia trochoidcs. 
(From Frestwicli’s “ Goolog}’.”) 
shows a great change ; all the Palaeozoic genera have given 
place to normal representatives of existing families and 
genera, such as Isastraea and Montlivaltia (Figs. 24 h, 25 h). 
The collections from the Inferior Oolite are richer, and the Table-case 
representatives of modern genera are increased by Fungians, 3. 
such as Thamnastraea, and also by a doubtful s]iecies(Fig. 24 a) 
representing the confluent Astraeids, in which the polyps 
and calyces are incompletely separated as in the Brain- 
coral. In the rocks of Bathonian age are many corals of 
similar type, the chief reef-builder being Calamophylla 
rculiata. In the Corallian rocks true reefs are formed of Table-case 
llicco.wiilia, Thamnastraea, and Isastraea, of which large 
specimens are shown (Fig. 25). Tlie structure of all these Wall-case 
•Turassic corals, as of the succeeding Cretaceous and Tertiary 
genera, can be gathered from the diagrams placed in the 
Table-cases. An interesting series is that of Isastraea oblonga. 
