24 
TRIBE I. ASTR^ACEA. 
b. Cellules of the stars in a transverse section scarcely decompound or 
not at all so. 
I. Ridges sulcate or entire, lamelloe unequally exsert. 
*34. A. versipora. *37. A. deformis. 
*35. A. denticulata. *38. A. varia. 
*36. A. pectinata. 
II. Ridges narrow, entire, nearly naked at summit, lamellcB unequal, hut 
hardly at all exsert, cellules of stars sometimes sparingly decompound. 
*39. A. rigida. 
III. Ridges entire or sulcate, lamellce even ; cells not coj’onate within, cellules 
of stars not decompound or scarcely so. 
40. A. reticularis. *42. A. purpurea. 
*41. A. petrosa. *43. A. pulchra. 
IV. Ridges entire, lamellce even, cells coronate within ; cellules of stars sim- 
ple [cells often very regularly polygonal). 
44. A. pentagona. 
*45. A. favistella. 
*46. A. eximia. 
*47. A. sinuosa. 
48. A. melicerum. 
*49. A. parvistella. 
*50. A. favulus. 
*51. A. cerium. 
*52. A. intersepta (hardly coronate). 
B. ERECT LOBED. 
*53. A. abdita. *55. A. robusta. 
*54. A. tesserifera. 
C. UNARRANGED SPECIES. 
56. A. complanata. 
57. A. heliopora. 
58. A. Hemprichii. 
59. A. halicora. 
*60. A. cyclastra. 
61. A. favosa. 
Subgenus I. — ORBICELLA. 
1. A. Orbicella radiata (Ellis). — Convex. Corallum with the calicles 
1 to 1^ lines distant, cylindrical, 5 to 6 lines broad, rounded at the margin ; 
interstices concave, radiately striate; cells deep; lamellae narrow. 
West Indies. — Ellis and Solander. Lamarck. 
2. A. Orbicella argus (Lamarck). — Subhemispherical, polyps mostly 5 
lines broad, a little prominent, with 48 internal lamellae. Corallum nearly 
solid ; calicles very short, conical, polygonal, 1 line high, exterior crowdedly 
and very evenly striate and denticulate ; cells circular, 3 lines broad, rather 
