SUMMARY OF RESULTS. 189 



account for the fact that we have, in the National Collection, corals even of different genera 

 gi-owint; side by side, so like one another, not only in habit but even in deeper skeletal 

 texture, that only an expert can tell the one from the other. In two instances only * is it at 

 present known that they are from the same localities. We have other instances of close 

 resemblance between specimens of different genera,t and I fully expect, as these researches 

 continue, to discover that for these also the environments were similar. 



The chief results, then, are practically all that could be expected from the relatively small 

 amount of the material. They are almost exclusively morphological, phylogenetic and 

 biological. The systematic arrangement of the forms in the order of their evolution cannot 

 yet be attempted. 



* See p. 72. f See p. 180. 



