THE GENUS ALTEOPOEA WITH THE FAVOSITID^. 515 



I am aware that in tlie foregoing notes I have ventured over 

 and over again into very debatable ground, and have touched 

 upon mauy subjects which I had no intention of elaborating on 

 the present occasion. I do not, indeed, pretend to be competent 

 to do this. My object in thus briefly and perhaps somewhat 

 prematurely stating these conclusions as to the fundamentals of 

 the morphology of the coral skeletOQ are . two, — first to make 

 clear why I consider Alveopora far removed from Pontes and 

 Goniopora, and allied rather to the Palaeozoic Favosites ; and, 

 secondly, because I think it due both to myself and to my fellow- 

 workers in Coral morphology to state the standpoint at which I 

 have arrived. Having before me the colossal task of rede- 

 scribing and rearranging the Madreporaria, my object in so doing 

 is to obtain, by inviting criticism, a truer conception of the 

 evolutionary processes to which the differeat families owe their 

 origin. 



A detailed comparison of the phylogenetic development of the 

 Madreporarian skeleton here set out with the schemes of Ort- 

 mann*, v. Kocht, and Miss Ogilvie J would involve a long and 

 largely profitless discussion. Even when I most differ from 

 them, I sincerely acknowledge the help I have received from 

 them. 



PosTSCEiPT. — Coralla builfc up solely of epitheeal cups seem to 

 have been formed in other ways than that described by Beecher 

 {I. c. anted). " £eaz<TO072ifz« " [c/. lleuss, Novara Exp. (Greol.) ii. 

 Taf. iii. fig. 9] appears to have been such a colony, and can, I 

 think, best be explained as built up by the overflowing method 

 above described. This would give the thin double wall found 

 here and in Favosites. But we still have the mural pores and 

 the horizontal spiny septa uniting Favosites with Alveopora. 



EXPLANATION OF PLATE 33. 



Tig. 1-1 a. View from the side and from above of the skeleton of the youngest 

 or parent polyp-stage of the genus Alveopora. The cup has been 

 bent round towards the light. A few septal spines are seen far down 

 the cup. Magniiied about 15 diameters. 



* Zeits. wiss. Zool. 1890, p. 278. 

 t Gegenbaur's Festschrift, p. 272. 

 + Phil. Trans, vo'. 187 1896, p. 316, 



