17a M ADREPORARI A . 



G. Viccnm 4-. 



G. Vicenza .5. Septa so wavy as to obscure the radial symmetry. 



G. Vicenza 8. 



G. Vicenza 9, 



G. Turin 1. 



(d) When the colony is very thin, the whole skeleton is reduced in size, and the walls are 



nearly flush with the surface. 



a. The surface is composed of a mosaic of granules, whicli are the tips of the 

 dwarfed vertical trabeculae. 

 G. North- West Australia 2. 

 G. China Sea 2. 

 G. Maldives 1. 

 G. Paris Basin 2. 

 y8. The surface is composed of horizontal flakes, the horizontal skeletal elements 

 being developed at the expense of the vertical trabeculse. 



G. China 'Sea 3. A Porites showing the same specialisation conies 

 from the same locality. Cf. G. Paris Basin 6. 



(e) If the encrusting colony deepens, then the walls tend to rise in height and to be 



thinner and sharper, and tlie septal formula may be obscured by the greater depth 

 of the calicles. 



G. Great Barrier Reef 9. 



G. Great Barrier Reef 11. Perhaps to B (6). 



G. North- West Australia 4- 



G. Verona 2. 



G. Paris Basin 1. 

 Doubtful ; — 



G. Egypt 1. 



The thickening of the stocks is associated with the formation of calicles with high walls 

 as described under the next heading. But before leaving the primitive type of calicle and its 

 variations, it should be re-stated that, whenever thin edges of colonies, no matter of what form 

 of growth, start expanding, the calicles produced are always of the primitive tyj^e. But in 

 every case these new calicles also show clear traces of the habit of the calicles typical of the 

 particular colony to which they belong. Instances of this may be seen in the illustrations, 

 cf. PI. II. figs. 2 and 3, PI. lil. figs.^ 7 and 8, PI. V. figs. 1 and 2, PI. VI. figs. 1 and 2, 

 PI. VIII. figs. 1 and 2, etc. 



B. Calicles with High Walls. 



The increased height of the wall leads to the deepening of the fossa, and the sinking away 

 of the intracalicular skeleton, which is variously modified and obscured. 



(a) Walls tliick. 



a. Showing radial symmetry in their component elements. 



G. Tonga Islands 1 



G. Tonga Islands 2 \ , ,. , i -r^ / i oa\ 



n rr 7 7 7 „ but tendmg towards D (p. 180). 

 G. Tonga Islands 3 \ " 



