INTRODUCTION. xxxix 



Section IV.— ASTREIN^E AGGREGATE. 



Corallum composite, massive, increasing by gemmation or by fissiparity. and in that 

 case not presenting a linear mode of arrangement of the corallites, which are always com- 

 pletely united laterally, but remain well defined, and never lose their individuality, as in 

 the confluent Astreina. 



57. Genus Astrea. 



{In parte) Lamarck, Syst. des Anim. sans Vert., p. 371, 1801 ; Milne Edw. and J. Haime, Comptes rend., 



t. xxvii, p. 494, 1848. 



Corallum massive, in general convex or sub-globose. Gemmation extra-calicular. Coral- 

 lites tall. Calicules having a free, exsert, obtuse, circular margin ; fossula not very deep. 

 Columella spongy, and not projecting at the bottom of the calicule. No pali. Septa 

 complete, exsert, broad, and strongly dentated or lobated ; the largest of their apical teeth 

 near the columella ; their sides strongly granulated. Costa highly developed, and com- 

 posed of lamellae ; in general perforated, and united by numerous dissepiments. 



Typ. sp., Astrea cavernosa, Milne Edw. and J. Haime, loc. cit., vol. x, tab. ix, fig. 1 ; Madrepora 

 cavernosa, Esper, Pflanz. Suppl. Mad., tab. xxxvii ; Astrea argus, Lamarck, Hist, des Anim. sans Vert., 

 t. xi, p. 259. 



58. Genus Cyphastrea. 



Milne Edw. and J. Haime, Comptes rend, de l'Acad. des Sc, vol. xxvii, p. 494, 1848. 



Corallum massive, convex, and globose. Gemmation extra-calicular. Corallites united 

 by a compact septal ccenenchyma, the surface of which is strongly granulated, or even 

 echinulated. Calicular rims as in the preceding genus. Columella papillose, and well 

 developed. Septa lamellar near the wall, but cribriform towards the columella, where 

 they are formed by a series of oblique processes, representing a sort of lattice ; their 

 calicular teeth rather larger towards the cahce than near the walls. 



Typ. sp., Cyphastrea microphtholma, Milne Edw. and J. Haime, Ann. des Sc. Nat., 3 me serie, vol. x, 

 tab. ix, fig. 5 ; Astrea microphtholma, Lamarck, op. cit. 



59. Genus Oulastrea. 



Milne Edw. and J. Haime, Comptes rend., t. xxvii, p. 495, 1848. 



Corallum massive and incrustating. Gemmation extra-calicular. Corallites low. 

 Calices circular, with a free margin. Columella papillose, and appearing to be formed by 

 the inner apical teeth of the septa. No pali. Septa with a crispate, denticulated, apical 

 margin, and echinulate sides. Costa also echinulate and crispate. 



Typ. sp., Oulastrea crispata, Milne Edw. and J. Haime, Ann. des Sc. Nat., 3 me serie, vol. x, tab. ix, 

 fig. 4 ; Astrea crispata, Lamarck, Hist, des Anim. sans Vert., vol. ii, p. 265. 



