38 VERRILL ON THE POLYPS OF THE 



Leaving Turbinolidcc out of consideration for the present, the Astr^earia may be arranged 

 as follows : — 



A. Fissiparous Astr.earia, embracing three families. 



I. EusntiUnoB M.-Edw. and H, having the edges of the septa entire, without paliform 

 lobes ; polyps with the disk in expansion raised above the coral ; tentacles well developed, 

 cylindro-conical. 



II. Lithophyllhm, corresponding to a part of Lithophylliacew M.-Edw. These have the 

 edges of the septa divided into strong teeth or spines, without paliform lobes ; disk level 

 with the top of the cells ; tentacles surmounting the top of the septa, short, conical, 

 numerous (3fn$$a, Isophyllia, etc.). 



III. Mimndrince, including part of Lithophylliacco? M.-Edw., viz.: Mceandrina, Manieina, Hydno- 

 phora, Tridacophyllia, Colpophyllia, etc., together with Faviacece. In these the septa have 

 their edges finely toothed or crenulate, with a paliform lobe towards the base. The small 

 tentacles are placed at the top of this paliform lobe, and the disk extends across the cells 

 even with the top of the paliform lobes, and does not rise level with the summit of the 

 walls. 1 



B. Gemmiparous Astr^earia, containing four families. 



IV. Stylinince,, corresponding with SiyHnacece M.-Edw. and Haime. Septa with entire 

 edges ; dissepiments well developed ; coenenchyma absent. 



V. Astrceince, embracing only a part of the same group as limited by Milne-Edwards and 

 Haime, viz : Astrceacece (pars), Cladoeoracece, Astrangiacece. These have dentate septa, rudi- 

 mentary coenenchyma, dissepiments usually well developed. 



VI. StylopJwrince M.-Edw. and H., including Stybphora, 31adracis, etc. In these there is 

 a well-developed coenenchyma, uniting the polyps, which is most compact at the surface. 

 The cells have a tendency to fill up at the surface and remain more open below. Septa 

 mostly entire. 



VII. Oculinidce, corresponding to the same group of Milne-Edwards and Haime, with the 

 addition of Distichopora and, perhaps, Errina. The cells have a tendency to fill up com- 

 pletely from below by deposition of solid matter ; dissepiments not very well marked ; 

 coenenchyma well developed, compact. 



Of these only the fifth and last are represented within our limits, so far as now known ; 

 yet species of all the others, except Siylinmce, occur about the Florida Reefs. 



Family Astr.ein.e Milne-Edwards. 



We have restricted this name, as indicated above, to but a small part of the forms in- 

 cluded by Milne-Edwards and Haime. This has been done principally from a consideration 

 of the structure of the soft parts. In this respect this group differs widely from most other 

 Astraddce, agreeing more nearly with Ocidina than with any other division that I have had 

 an opportunity to examine. The upper portion of the polyp has the power of rising out 



l This peculiar character, which separates M&xmdrina: alcohol, and with the figures of the living polyps of Mussa 



from Litkophijllina:, I have ascertained from numerous ex- and Symphyllia in Dana's Zoophytes. The polyps of Mce- 



aminations and dissections at the Museum of Compara- andrina have also been well figured by LeSueur, Dana, 



tive Zoology of alcoholic specimens of Maandrina, Mani- and others. 

 cina, and Fauia, compared with hophijllia dipsacea, also in 



