TRIBE I. — ASTR^ACEA, 
35 
5L AstRjEa cerium {Dcma). — Corallum subceilular, firm; cells angular, 
lines broad; ridges quite narrow: in a transverse section, stars scarcely 
multiradiate (about 12 larger rays) with simple open cellules ; septa solid, 
nearly i a line thick : in a vertical section, cellules nearly equal, h a line 
broad, and septa linear and solid. 
Plate 13, fig. 8. — Wake’s Island, Pacific Ocean. — Exp. Exp. 
52. Astr^a intersepta [Esper). — Convex; disks often budding and di- 
chastic. Corallum cellular, firm; cells minute, nearly circular, less than a 
line broad, rather shallow, scarcely cornate within ; ridges flat, sometimes du- 
plicate, lamello-scabrous ; lamella3 a little exsert and radiate around the cells 
upon the septum, truncate at apex, fragile, abrupt within : in a transverse sec- 
tion, stars few-rayed, with the cellules simple ; septa i to ^ of a line thick, 
subceilular, cellules interruptedly in a single series. 
Plate 13, fig. 12, surface of corallum, natural size; 12 a, cells enlarged ; 
126, lamellae and section of cell, natural size; 12c, lamellae enlarged; 12c?, 
transverse section enlarged; 12e, vertical section, natural size. — East Indies. 
— Exp. Exp. 
53. x\str^a abdita (Ellis). — Glomerate, gibbous or lobato-ramose and 
angular. Corallum with angular cells, 4 to 6 lines wide, shallow, patulous ; 
ridges acute and often thin ; lamellae crenulato-dentate. 
East Indies. 
54. Astr.ea tesserifera (H. Ehrenherg). — Glomerate, erect, lobed 
and polygonal ; fuscous. Corallum cellular, rather light ; cells angular, 5-6 
lines broad, shallow, patulous, not coronate within ; ridges rather stout and 
triangular, apical thin and often pellucid ; lamellae srongly denticulate : in a 
transverse section, stars multiradiate, septa nearly solid. 
Plate 13, fig. 9a, 6, c, sections of cells, natural size; showing profile of la- 
mellae ; 9 c?, transverse section of corallum, natural size. — Red Sea..—Ehrenhe7g. 
55. Astr^a robusta (Dana). — Lobed glomerate, lobes ascending and 
polygonal, as in the tesserife^'a. Corallum firm and little cellular ; cells 4 to 6 
lines broad, angular, shallow, patulous, short coronate within ; ridges triangu- 
lar ; lamellae narrow, spinoso-denticulate : in a transverse section, stars multi- 
radiate, and rays closely crowded, with minute cellules ; septa nearly solid. 
Plate 13, fig. 10, part of corallum, natural size; 10 a, section of cells, show- 
ing profile of lamellae ; 10 6, the same enlarged; 10 c, transverse section of 
corallum, natural size ; 10 d, vertical section of same. — Feejee Islands. — 
Exp. Exp. 
56. Astr^a complanata (H. Ehrenherg). — Effuse; brown. Corallum 
pulvinate, spinulous ; cells large, 4i to 5 lines broad, nearly circular, plane ; 
interstices narrow, depressed, every where obsolescent 
The Red Sea. — Ekrenberg. 
