212 ZOOPHYTES. 



II. Caliculis parvulis, 2'" angustioribus. 



8. A. ORBICELLA HYADES. (Dana.} 



A. convexa, arrecto-glomerata ; polypis vix 2'" latis, lamellis 24. Co- 

 rallum percellulosum ; cettis orbiculatis, 1J'" latis, margine annulato 

 (sicut in pleiades) ; lamellis tenuissimis ; inter stitiis angustis, sapius 

 concavis : transverse secto, stellis 24,-radiatis ; septis valde cellulosis. 



Convex, erect glomerate and gibbous ; polyps scarcely 2 lines broad, 

 with 24 internal lamellae. Corallum light cellular ; cells circular, 

 1J lines broad, with the margin annulate as in the pleiades ; lamellae 

 very thin ; interstices narrow, mostly concave : in a transverse sec- 

 tion, stars with 24 rays, septa spongy cellular. 



Plate 10, fig. 15, transverse view, natural size. 



West Indies. Boston Nat. Hist. Soc. 



This species resembles the pleiades, but the stars of the worn sur- 

 face are larger, and have twenty-four nearly equal rays, the interme- 

 diate not being obsolete. The interstices in a vertical section are very 

 delicately cellular and irregularly so, as the rays of the stars seem to 

 be interrupted. In the transverse section, the septum contains gene- 

 rally a single imperfect series of delicate cellules which are seldom 

 angular. In these last characters the species approaches the Caryo- 

 phyllacea. The cellules of the stars are deep and never decompound. 

 The rays meet in a very narrow fund us which is scarcely convoluted. 

 The specimen affording this description is a subturbinate mass six 

 inches high, four and a half wide at top, with the summit nearly 

 flat. 



9. A. ORBICELLA EXCELSA. (Dana.) 



A. arrecto-glomerata, 5" alta et 2" lata ; polypis parvulis, (vix 2'" latis} 

 lamellis 24. Corallum robustum ; cettis orbiculatis, vix l'" latis, 

 margine prominulo, 24 lamellis sub&qualibus, denticulatis ; inter stitiis 

 sfepius '" latis : transverse secto, stellis fere 1<-radialis ; septis par ce 

 cellulosis, interdum cellulis uniseriatis. 



