134 On the Interrelationships of the Madveporidge. 



Madreporinse. The chief objection to this rests in the 

 specialized character of the laminate radial structures of 

 Astrceopoi-a, which ought, perhaps, to separate that genus 

 from Madrepora and Turhinaria. In the meantime, how- 

 ever, they can be usefully united in the manner suggested. 



I therefore suggest the following arrangement of the 

 family : — 



Family Madreporidae. 



Subfamilies: I. Madeepobin^. II. Montiporinje. 



Genera : Madrepora. Turhinaria. AstrcsojJora. Montipora. Anacropora. 



A serious objection may be raised to this description of the 

 phylogeny of the Madreporid^, viz. that it is apparently 

 based exclusively upon study of the five genera dealt with. 

 It is true that such a limitation of one's survey makes all 

 generalizations hazardous. I am, however, encouraged to 

 state the conclusions I have arrived at with regard to these 

 genera even at this early stage because they are not based 

 solely upon study of the five genera concerned. Most of the 

 other Madreporarian genera — at least, the better known of 

 them — have been studied and compared again and again for 

 the express purpose of arriving at some clear insight into the 

 different lines along which the stony corals have been diffe- 

 rentiated. I am aware that this does not appear from 

 anything said in this paper. I have, however, here pur- 

 posely abstained from making any definite morphological 

 statement about any genus which I have not studied syste- 

 matically. The survey of a io.w specimens of any particular 

 genus may give reliable hints for guidance towards a better 

 understanding of the genera which are at the time the object 

 of close study, but cannot be exact enough to admit of definite 

 assertion. It is, indeed, quite possible that when all the 

 available specimens of the genus Porites have been under 

 review, the purposely very limited reference to the morphology 

 of that genus given above may have to be qualified. 



