78 PERCY SLADEN TRUST EXPEDITION 



1879. Favia, Klunzinger, Korall. Roth. Meer., iii, p. 25. 



1879. Ooniastrcea (pars), Klunzinger, Korall. Roth. Meer., iii, p. 32. 



1879. Prionastrcea, Klunzinger, Korall. Roth. Meer., iii, p. 36. 



1879. Acanthastrcea, Klunzinger, Korall. Roth. Meer., iii, p. 42. 



1879. Orhicella (pars), Klunzinger, Korall. Roth. Meer., iii, p. 47. 



1884. Favia, Duncan, Journ. Linn. Soc. London, Zool., xviii, p. 100. 



1884. Heliastrcea (including subgenus Ulastrcea), Duncan, Journ. Linn. Soc. London, Zool., xviii, p. 104.' 



1884. Phyniastrma, Duncan, Journ. Linn. Soc. London, Zool., xviii, p. 106. 



1884. Plesiastrcea, Duncan, Journ. Linn. Soc. London, Zool., xviii, p. 107. 



1884. Acanthastrcea, Duncan, Journ. Linn. Soc. London, Zool., xviii, p. 119. 



1884. Prionastrcea, Duncan, Journ. Linn. Soc. London, Zool., xviii, p. 123. 



1899. Astrcea, Gardiner, Proc. Zool. Soc. London, p. 747. 



1899. Orhicella (pars), Gardiner, Proc. Zool. Soc. London, p. 751. 



1899. Prio7iastrcea, Gardiner, Proc. Zool. Soc. London, p. 757. 



1900. Favia, Vaughan, Monogr. U.S. Geol. Surv., xxxix, p. 154. 

 1904. Favia, Gardiner, Fauna Geogr. Maldives and Laccadives, p. 766. 



1904. Orhicella (pars), Gardiner, Fauna Geogr. Maldives and Laccadives, p. 774. 



1904. Stephanococnia, Gardiner, Fauna Geogr. Maldives and Laccadives, p. 784. 



1904. Acanthastrcea, Gardiner, Fauna Geogr. Maldives and Laccadives, p. 784. 



1904. Prionastrcea (pars), Gardiner, Fa\ina Geogr. Maldives and Laccadives, p. 785. 



1906. Favia, Marenzeller, Exp. "Pola," Rot. Meer., Riffkorall., Zool. Ergeb. Wien, xxvi, p. 56. 



1906. Orhicella (pars), Marenzeller, Exp. "Pola," Rot. Meer., Riffkorall., Zool. Ergeb. Wien, xxvi, p. 60. 



Corallmn. Massive or incrusting, varying considerably in form of growth. Corallites 

 polygonal, oval, circular or distorted, usually separated by perithecal regions of varying 

 thickness, level or projecting with distinct rims, sometimes with walls completely fused as 

 in Goniastrea. Calices varying much in size, from 2 to 20 mm. or more in diameter. 

 Septa without any cyclical arrangement, varying considerably in number and nature in 

 the different species. Costse present when walls project, those of neighbouring corallites 

 usually meeting along the middle of the intervening perithecal regions. Columella formed 

 of septal trabeculee, a rudimentary to well developed compact structure. 



Polyps. Varying in shape and size as the corallites. Mesenteries without directive 

 couples, and without regular alternation, principal couples 6 — 12, varying only slightly 

 in number in each species. Subsidiary couples from same number as principal couples 

 to more than twice as many, varying much in number in the same species, also in relative 

 height and width, this variation due to continued addition of new mesenteries in the 

 course of polyp-growth, some of the later ones being so short as not to extend below the 

 stomodaeal regions of polyps. Stomodeeum laterally compressed, no directive grooves, 

 its ridges varying considerably in width and thickness. Every tentacle with a large 

 terminal battery and from three to eight much smaller sub-terminal ones. Entocoelic 

 pleats varying much in size, shape and distribution. All types of nematocysts excepting 

 II c and III 6 present. Stomodseal endoderm very thin. Ova occurring in both principal 

 and subsidiary mesenteries. 



Multiplication as a rule by fission, sometimes aided by budding. 



Remarks. I agree with Vaughan that the name Favia as originally employed 

 by Oken should be retained for section I of Lamarck's Astrea, typified by Madrepora 

 rotulosa, Ell. and Sol. 



This genus has a wide range of variation — as is seen from a comparison of two 



