MATTHAI— RECENT COLONIAL ASTR^ID^ 103 



elongated, slightly projecting, with distinct rims, usually "5 — 1 mm. apai't (towards edges 

 of corallum up to 2 '5 mm.), separated by somewhat polygonal furrows. Calices varying 

 little in size, 2 or 2 '5 mm. in diameter, shallow, not more than 1 mm. 



Septa thickening towards walls, with vertical ragged edges, spinulose or coarsely 

 rough sides, "5 — "75 mm. exsert, 14 — 24 in number, 7 — 13 meeting columella, narrow, — 

 some of these sometimes thicker than the others — mostly with rough, blunt paliform lobes, 

 perforated behind. Exsert ends of septa arched. Gestae conspicuous, spinulose, usually 

 stopping at inter-corallite grooves, sometimes those of adjacent corallites meeting in 

 notches. A cycle of very narrow septa alternating with the principals and subsidiaries 

 usually without costse. Columella varying in texture, being compact or spongy, and ^ — ^ 

 width of calyx, in some corallites quite rudimentary. 



Multiplication by unequal or equal fission. 



The hillocky mode of growth and the shape of the hillocks are quite characteristic of 

 this species. It is also comparatively compact, varying only within narrow limits. 



The polyps were all in a badly-preserved condition ; two were sectioned from a 

 specimen from Rotuma, in one of them 6 principal couples of mesenteries and 9 subsidiary 

 couples were counted. Tentacles were present over all the entocoeles and exocoeles. 



Remarks. Corallum. In the Paris Museum there are 2 specimens from the Indian 

 Ocean, referred by Milne Edwards and Haime to HeliastrcBa acropora, one a broken off 

 hump (15 X 11 cm.), the other a large hillocky specimen (23x 19x16 cm., PL 26, fig. 4), 

 and 4 examples from Red Sea (all humps, the largest 10 x 7'5 cm.) to Favia lohata. In 

 the Berlin Museum are small examples referred by Klunzinger to Favia lobata, 2 of 

 which he has figured. Marenzeller has assigned 3 specimens of the "Pola" expedition to 

 Orbicella lobata, one of which, measuring 48 x 37 x 26 cm., is an excellent example with 

 crowded hillocks, the latter up to 10 cm. high. 



Localities. Chagos : Salomon (13); Egmont (2). Amirante (1 from over 25 fms.). 

 Seychelles (1). Aldabra (l). Eunafuti (3). Rotuma (l). Also from Red Sea (Milne 

 Edwards and Haime, Klunzinger and Marenzeller), ? loc. (Esper, Linnaeus and Oken). 



12. Favia vebsipora (Lamarck). (PI. 23, fig. 3 ; 25, figs. 5, 6 and 9 ; 37, fig. 3.) 



1816. Asirea annularis, var. 2, Lamarck, Hist. Anim. sans vert., ii, p. 259 ; 2** edit., p. 405 (non Madrepora 



annularis, Ellis and Solander). 

 1816. Astrea versipora, Lamarck, Hist. Anim. sans vert., ii, p. 264; 2" edit., p. 414. 

 1830. Dipsastrea versipora, Blainville, Diet. Sci. Nat., Ix, p. 338; Man. d'actiiioL, p. 373. 

 1833. Astrea annularis, Quoy and Gaimard, Voy. I'Astrol., Zooph., p. 210, p]. 17, figs. 17 — 18. 

 1850. Astrea laperousiana, Milne Edwards and Haime, Ann. Sci. Nat., Zool., ^^ ser., xii, p. 101. 

 1850. Astrea annuligera, Milne Edwards and Haime, Ann. Sci. Nat., Zool., 3^ ser., xii, p. 103. 

 1850. Plesiastrea versipora, Milne Edwards and Haime, Ann. Sci. Nat., Zool., 3^ ser., xii, p. 118 (non Orbicella 



versipora, Gardiner). 

 1 1850. Plesiastrea quatrefagiana, Milne Edwards and Haime, Ann. Sci. Nat., Zool., 3*^ ser., xii, p. 119. 

 1857. HeliastroBa laperouse.ana, Milne Edwards and Haime, Hist. Nat. Corall., ii, p. 460. 

 1857. Heliastrcea annuligera, Milne Edwards and Haime, Hist. Nat. Corall., ii, p. 471. 

 1857. Plesiastrcea versipora, Milne Edwards and Haime, Hist. Nat. Corall., ii, p. 490, pi. D7, fig. 5. 

 ? 1857. PlesiastrcBa quatrefagesana, Milne Edwards and Haime, Hist. Nat. Corall., ii, p. 491. 

 1899. Orbicella acropora (pars), Gardiner, Proc. Zool Soc , p. 752. 

 1899. OrhiceUa annuligera, Gardiner, Fauna Geogr. Maldives and Laccadives, p. 774, pi. 63, tig. 32. 



