118 PERCY SLADEN TRUST EXPEDITION 



25 — 30 turns of the spiral in each. Filaments are present on all the principal 

 mesenteries and the wider subsidiaries ; nematocysts I occur in small numbers along their 

 whole lengths ; II c nematocysts are numerous, as closely arranged in the convolutions as 

 III h in Echinopora. Type III is absent. The endoderm in the oral-disc is as thin as the 

 ectoderm over it, in the tentacles vacuolated and lobed with numerous algae, in the 

 mesenteries somewhat swollen on each side of the thickened region of the mesoglaea, 

 beyond which it is thin. Algae are scarce in the mesenterial endoderm. Gonads were not 

 present in any of the polyps. The polyps of this species bear greater resemblance to those 

 of G. pectinata than to those of G. retiformis, although the condition is reversed with 

 regard to the corallum. 



Number of polyps examined three, from a specimen from Amirante, 16 fms. 



B. Corallum. Klunzinger's suggestion that Madrepora solida, Forsk. was a 

 Porites has later been confirmed by Marenzeller's examination of Forskal's type-specimens 

 in the Copenhagen Museum. Marenzeller has also made the discovery that Madrepora 

 favus, Forsk., is not a Goniastrea. Of the two specific names I have retained the former 

 since it comes first in Forskal's paper. I could not examine Klunzinger's type-specimen of 

 G. favus, as it was not in the Berlin Museum, but judging from his figure it appears to 

 belong to the present species. Of the five specimens referred by Milne Edwards and 

 Haime to G. solida (2 from Bed Sea and 3 from Seychelles) two (one from each locality) 

 belong to G. retiformis, the figured specimen (Ann. Sci. Nat., 3*" ser, x, pi. 9, fig. 7) being 

 one of them ; all these specimens were later re-named G. favus by Klunzinger. 



In the Hofmuseum, Vienna, are 19 specimens ("Pola" expedition) referred to 

 G. favus by Marenzeller,. of which 12 are numbered; of these nos. 15919, 15921, 15922 

 and all the unnumbered specimens are undoubtedly G. retifo7-mis. The remaining ones 

 may be assigned to G. solida; no. 15918 has corallites showing a meandering tendency. 



Localities. Seychelles (l). Maldives, Hulule (1). Amirante (1 small, 16 fms.). 

 Known also from the Bed Sea (Milne Edwards and Haime, and Marenzeller). 



2. Goniastrea retiformis (Lamarck). (PL 10, fig. 3 ; 31, figs. 1 — 5 ; 33, fig- 3 ; 

 38, figs. 2 and 4.) 



1816. Astrea retiformis, Lamarck, Hist. Anim. sans vert., ii, p. 26.5 ; 2^ ^dit., p. 415. 



1834. Astrea spongia, Ehrenberg, Corall. roth. Meer., p. 96. 



1850. Goniastrea solida (pars), Milne Edwards and Haime, Ann. Sci. Nat., Zool., 3^ ser., xii, p. 160. 



1850. Goniastrea retiformis, Milne Edwards and Haime, Ann. Sci. Nat., Zool., 3'* ser., xii, p. 161. 



1850. Goniastrea hournoni, Milne Edwards and Haime, Ann. Sci. Nat., Zool., 3'' ser., xii, p. 162. 



1857. Goniastrcea solida (pars), Milne Edwards and Haime, Hist. Nat. Corall., ii, p. 444. 



1857. Goniastrcea retiformis, Milne Edwards and Haime, Hist. Nat. Corall., ii, p. 446. 



1857. Goniastrcea bournoni, Milne Edwards and Haime, Hist. Nat. Corall., ii, p. 446. 



1879. Goniastrcea retiformis, Klunzinger, Korall. Roth. Meer., iii, p. 36, pi. 4, fig. 5. 



1889. Goniastrcea retiformis, Ortmann, Zool. Jahrb., iv, p. 527. 



? 1879. Goniastrcea favus (pars), Klunzinger, Korall. Roth. Meer., iii, p. 35, pi. 4, fig. 4 and pi. 10, fig. 7 (non 



Madrepora favus, Forsk.). 



1892. Goniastrcea retiformis, Ortmann, Zool. Jahrb., vi, p. 661. 



1899. Goniastrcea eximia, Gardiner, Proc. Zool. Soc. London, p. 747. 



1899. Goniastrcea solida, Gardiner, Proc. Zool. Soc. London, p. 747. 



1904. Goniastrcea retiformis, Gardiner, Fauna Geogr. Maldives and Laccadives, p. 772. 



