28 
TRIBE I. ASTR^ACEA. 
Subgenus II.— SIDERINA. 
17. A. SiDERiNA GALAXEA ( EZ/'i5).~Incrustating and glomerate, sometimes 
subglobose. Corallum subcellular ; cells immersed, rather deep, mostly li 
lines broad, lamellae very narrow, and very minutely denticulate, 6 to 10 a 
little more prominent than the others ; septa plane, scarcely a line broad, very 
closely and finely lamello-striate : in a transverse section, stars polygonal, 
mostly 2 lines broad, erowdedly multiradiate, with the centre solid. !] 
Plate 10, fig. 12, surface of corallum natural size ; 12 «, same, another 
variety ; 12 h, transverse section of the variety fig. 12, natural size ; 12 c, same 
enlarged ; 12 of, transverse section of the variety fig. 12 a , — West Indies, 
Martinique. Lamouroux. — East Indies, Lamarck, Acad. JVat. Sci. Philad. 
Subgenus III.— FISSICELLA. 
18. Astr^.a speciosa (Dana). — Hemispherical ; polyps a little prominent, 
4 to 6 lines broad. Corallum light cellular; calicles usually subcylindrical, 
and 1 to .1^ lines prominent, often somewhat remote, margin neatly rounded ; 
cells deep, abrupt within, and scarcely at all coronate ; lamellsB neatly even 
and denticulate: in a transverse section, stars many-rayed; rays very thin 
and cellules decompound; septa very cellular. 
Plate 11, fig. 1, part of the corallum, natural size; 1 a, vertical section of ^ 
cell, and profile of lamellae ; 1 b, lamellae enlarged ; 1 c, transverse section of 
corallum, natural size ; 1 d, vertical section, natural size. — East Indies. — Eup. 
Exp. 
19. Astra:a uva {Esper). — Polyps prominent and often 9 lines broad. Co- 
rallum with the calicles 1^^ to 2 lines prominent, subangular and rounded 
conical, contiguous (and hence the intermediate sulcus subacute) ; exterior 
erowdedly lamello-striate and denticulate; cells 4 to 5 lines broad, and often 
elongated. 
China Sea. — Esper, from M. Chemnitz. — Red Sea, Ehr'enherg. 
20. Astraia ananas {Ellis). — Subhemispherical ; polyps 3 to 5 lines broad. 
Corallum with rounded or convex calicles, subangular, often oblong, unequal, 
contiguous; interstices concave; cells 2 to 3 lines broad; lamellae denticulate. 
West Indies. — Ellis, Lamarck. 
21. Astra:a pandanus {Dana). — Subglobose, color dark brown ; polyps i 
an inch broad. Corallum quite cellular, with rounded calicles (as in the 
ananas), subangular, contiguous, subequal ; cells nearly circular, often oblong, 
3 to 4 lines broad, rather shallow, obsoletely coronate within ; lamellae even, 
finely denticulate within and without : in a transverse section, septa biseriately 
cellular ; stars many-rayed, Avith the cellules much decompound. 
