ANTHOZOA. 27 



The "chain-coral" Holy sites (fig. 4, n) and Syringopora (fig. 



4, io ) resemble, at first sight, the recent asteroid Tubiporidce : 

 in Halysites the radiating septa are quite rudimentary ; and 

 in Syringopora the tabulae are funnel-shaped, forming a central 

 axis to each tube. The Favositidw (fig. 4, 12) are mostly very 

 regular both as to their polygonal shape and transverse tabulae ; 

 the cells of adjacent corallites are connected by pores, either 

 in the sides or angles of the walls ; the septa are rudimentary. 

 In the genus Chcetetes the tubes are always slender, and much 

 elongated, and their walls imperforate. Miclielinia resembles 

 the fruit of the Nelamhium ; it has vesicular tabulae and 

 root-like processes to its basil plate. Heliolites (fig. 4, 9), of 

 which many species are found in the Silurian and Devonian 

 limestones, is related to the recent Milleporw. The radiating 

 septa are distinct, and the tabulae regular; the interspaces 

 between the stars are filled up with fine and regular tubes. 

 One genus of Fihngidm (Palceocyclus) occurs in the Upper 

 Silurian. 



The British secondary corals are not very numerous ; for 

 although specimens abound in the coral-rag districts, only 

 fourteen species are- found in that formation. Altogether, 

 sixty-five species are found in the English oolites, and twenty- 

 two in the chalk and greensands. These are mostly Astrceidw, 

 or related to Fungia. Three common forms in the oolites are 

 Montlivaltia (fig. 5, 9), Stylina (fig. 5, 10) and Thecosmilia (fig. 



5, 11). The English cretaceous strata afford the Holocystis 

 (fig. 5, 8), which is the most recent coral with quadripartite 

 septa of the polype-cell ( s') ; TrochocyatJms and Parasmilia 

 (fig. 5, 6), resembling the recent Cyathina ; and the little 

 " Fungia" coronula (fig. 5, 3), described in two genera (Micra- 

 oaeia and Stephanophyllia) of distinct orders in the " Mono- 

 graphs of the Palasontograpliical Society."' The lower chalk 

 of France and Germany contains many other corals, especially 

 Cy otolites (fig. 5, 5), P achy gym (fig. 5, 7), and Diploctenium 



