8 



PRor. p. MAETm Duncan's retision op tbe 



usually solid and imperforate. Theca or wall solid, may be epitlie- 

 cate. Septa solid near the wall, and usually, but not invariably, 

 solid at the further part. Interseptal loeuli open throughout, or 

 closed more or less by endotheca in the form of dissepiments, 

 tabulae, and stereoplasm. Calicos of different shapes. 



Soft parts : — One or more rows of tentacles in relation to tlie 

 septa and interseptal loculi» The disk with one or more oral 

 openings or mouths; a mesentery usually in each interseptal 

 loculus. Septa usually in multiples of six, or variable in tbe 

 number of their orders. 



The sclerenchyma, or hard calcareous part of the Madrepo- 

 raria Aporosa, may consist of the theca or wall of the corallite, 

 sometimes of a common colonial wall, of septa, pali, costse, of a 

 columella, of endotheca or dissepiments, tabulsB or synapticula, or 

 stereoplasm, and of exotheca, epitheca, and peritheca. There 

 may be basal expansions or mural or epithecal rootlets. The 

 epitheca may be free or united to the wall, or may be indistin- 

 guishable from it. 



Keproduction by ova, also by gemmation from different parts of 

 the corallum or colony, and increase may occur by fissiparity and 

 serial growth. 



Milne-Edwards and Jules Haime divided the section Madre- 

 poraria Aporosa into eight families — the TurbinolidsD, Dasmidse, 

 Oculinidse, Stylophoridse, Astrseidse, Eehinoporidse, Merulinacese, 

 and the Eungidse. 



Of these fauulies the Turbiriolidse, Oculinidse, and Astra3id£e 

 are retained. The first includes the old Dasmidss ; the second 

 takes in those StylophoridsB which remain after the elimination 

 of the true Stylasters according to H. N. Moseley. The Astrseid^e 

 absorb part of the Eehinoporidse and the Merulinacese. 



Another family is required, that of the Pocilloporidse, which 

 includes the genera Pocillopora and Seriatopora of the old Tabu- 

 lata, and is established upon the work of H. JN". Moseley and 

 Verrill. 



The subfamilies of the Turbinolidse of Milne-Edwards and 

 Jules Haime, depending on the presence or absence of pali, are 

 absorbed in this revision, and so are the two great divisions 

 of the Astrseidfe, which only depend upon the entire or dentated 

 condition of the edges of the septa. 



