I 5 2 MANUAL OF ZOOLOGY. 



One of the Ptnnatulidce (viz., Graphularia) has been found in 

 the London Clay (Eocene), and the same formation has like- 

 wise yielded two species of Gorgonidce. (Mopsea and Websteria}. 

 The genus Corallium has likewise been found in deposits of 

 Miocene age. 



The Ctenophora, being entirely destitute of any hard structures, 

 are not known at all as occurring in the fossil condition. 



APPENDIX GIVING A TABULAR VIEW OF THE DIVISIONS OF THE 



ZOANTHARIA SCLERODERMATA AND RUGOSA (AFTER 



MILNE-EDWARDS AND JULES HAIME). 



A. The Zoantharia Sderodermata are defined by the possession of a 

 sclerodermic corallum, the parts of which are arranged in multiples of five or 

 six. Septa generally well developed, but not combined, as a rule, with tabulae. 



The following chief divisions of the Zoantharia Sderodermata are, with 

 few alterations, those adopted by the above-mentioned authorities : 



I. TABULATA. Septa rudimentary or absent; tabulae well developed, 



dividing the visceral chamber into a series of stories. 



1. Thecidce, Corallum massive ; a dense spurious ccenenchyma formed 



by the lateral union of the septa ; tabulae numerous. 



2. Favositida. Septa and corallites distinct ; little or no true ccenen- 



chyma. 



3. Seriatoporidce. Corallum arborescent ; sclerenchyma abundant and 



compact ; tabulae few. 



4. Milleporidce. Corallum massive or foliaceous ; septa not numerous ; 



sclerenchyma tabular or cellular. 



II. PERFORATA, Septa well developed; no tabulae; dissepiments rudi- 



mentary ; sclerenchyma porous. 



5. EupsammidcE. Corallum simple or composite ; septa well developed 



and lamellar ; columella spongiose. 



6. Poritidce. Corallum composed of spongy, reticulated sclerenchyma. 



Septa never lamellar, but consisting wholly of a more or less definite 

 series of trabeculae ; no tabulae. 



7. Madreporida. Corallum usually composite ; cosnenchyma abundant 



and spongy ; thecae porous, not distinct from the ccenenchyma ; 

 septa distinct, but slightly perforate. 



III. APOROSA. Septa well developed, completely lamellar, and primitively 



consisting of six elements ; no tabulae ; sclerenchyma imperforate. 



8. Fungidce. Corallum simple or compound ; thecae ill developed, and 



somewhat porous) no dissepiments or tabulae ; synapticulae numerous. 



9. AstrceidcE. Corallum simple or compound ; no proper ccenenchyma ; 



numerous dissepiments ; no synapticulas. Corallites well denned, 

 and separated from one another by perfect walls. 



10. Oculinidce. Corallum composite ; ccenenchyma abundant and com- 



pact ; dissepiments few in number. Walls of the corallites without 

 perforations, not distinct from the ccenenchyma. 



11. Turbinolidtz. Corallum usually simple ; no ccenenchyma ; septa well 



developed ; no dissepiments, nor synapticulae. 



IV. TUBULOSA. Septa indicated by mere striae ; thecae pyriform ; corallites 



sometimes connected by a creeping basal ccenenchyma. 



12. Auloporida. This being the only family in the 7~ubulosa, its charac- 



ters are necessarily the same as those of the division itself. 



