ANTHOZOA 



23 



in the quadripartite character of their plaited cups or stars, 

 whereas the lamellee (or septa) of the uther families are deve- 

 loped in multiples of 6. A remarkable exception exists in the 

 Holocystis (fig. 5, s), an Astrea-like coral with quadripartite 

 stars, which is found in the lower greensand. The old-rock 

 corals are also remarkable for the maimer in which they are 

 partitioned off by horizontal " tabular" (fig. 4, 3), like the septa 

 of the Nautilus and Spondylus. This character obtains not 



Fig. 4. 



Palaeozoic Corals (Anthozoa). 



1. Aniplexus Sowerbyi, Ph. ; Carboniferous, Ireland. 



2. ( 'yathophyllum turLinatum, Lin. ; U. Silurian, Wenlock. 



3. Cyathophylluni subturbinatum (section); U. Silurian, Wenlock. 



4. Cystiphyllum Siluriense, Lonsd. ; U. Silurian, Wenlock. 



5. Zapbrentis Pbillipsi, M. Edw. ; Carboniferous, Somerset. 



6. Lithodendron irregulare, Ph. ; Carboniferous, Europe. 



7. Lithostrotion striatum, Flem. ; Carboniferous, Europe. 



8. Acervularia luxurians, Eicb. ; U. Silurian, Europe. 



9. Heliolites interstincta, Wabl. ; U. Silurian, Europe. 



1 o. Syringopora ramulosa, Goldf. ; Carboniferous, Europe. 

 1 1. Halysites catenulatus, L. ; Silurian, Northern Regions. 

 12. Favosites Gothlandica, Lam.; Silurian, North. 



only in the GyathophyllidoR, but also in the Mitteporidce, Favo- 

 sitidce, and other palaeozoic families. Of the 129 Silurian 

 corals, 121 belong to the tabulated divisions; 



