90 Proceedings of the Boyal Physical Society. 



Chcetetes, Fisclier; Dania, Edw. and H. ; Stenopora, 

 Lonsd.; and Constellaria, Dana. 

 Tribe 3. Ralysitince. Corallum composed of corallites 

 constituting vertical laminae or fasciculi, but more or 

 less free laterally, and united by means of connecting 

 tubes or mural expansions; walls well developed and 

 not porous ; septa distinct, but small. Genera — ffaly- 

 sites, Fischer ; Karmodites, Fischer (subsequently aban- 

 doned for Syringopora, Goldf.); and Thecostegites, E. 

 and H. 

 Tribe 4. PocilloporincB. — Corallum massive, gibbous, or 

 subdendroid, with thick imperforated walls, forming 

 towards the surface an abundant compact ca?nenchyma; 

 septa quite rudimentary, Genus — Pocillopora, Lam. 

 Family III. SERiATOPORiDiE. — Corallum arborescent or 

 bushy, with an abundant compact coenenchyma; visceral 

 chambers filling up by the growth of the columella and the 

 walls, and showing but few traces of tabul?e. Genera — 

 Seriatopora, Lam.; Bendropora, Mich.; Phahdopora, E. 

 and H. 



Family IV. Thecid^. — Corallum massive, with an abun- 

 dant, compact, spurious ccenenchyma, produced by the septa 

 becoming cemented together laterally; tabulae numerous. 

 Genus — Thecia, E. and H. 



Various additions, modifications, and improvements in the 

 above classification of the ''Tabulata" were made by Milne- 

 Edwards and Haime during the progress of their classical 

 monograph on the fossil corals of Britain ; many new genera 

 were added, and the tribe of the Stylophyllinco (to include the 

 Cretaceous Stylophyllum, Reuss) was inserted in the family of 

 the Favositidm. Most of the changes here indicated will be 

 found by those interested in the subject in the systematic 

 account of the "Tabulata" given by Milne-Edwards in his 

 masterly "Histoire Naturelle des Coralliaires" (vol. iii., 1860). 

 The first serious attack upon the classification of Milne- 

 Edwards and Haime, and upon the position of the " Tabulata," 

 was made by Professor Louis Agassiz, who in 1857 examined 

 the living animal of Millepora, and arrived at the conviction 

 that this well-known genus was truly Hydrozoal (Amer. 



