140 MADREPORARIA. 



The above are the only known Porites from these rej^ions which approach the coenen- 

 chymatous forms so common in the Indo-Pacific area, see Vol. V., Table III. And with 

 regard to these it is a matter of doubt whether, except in the case of P. West Indies x. 15, 

 tlie thick walled calicles are quite normal ; compare for example the observations on 

 P. Bahamas 1. 



B. Forms with three rings of trabeculse. The wall ring is always a zigzag, more or less 

 ]irnnounced. 



/'. Ca2x Verde Islands 1 (PI. I. fig. 2). The wall and septal granules sometimes 



touching, and sometimes distinct. This condition may indicate irregular 



perforations in the septa. 

 P. Cape Verde Islands 3 (PI. I. fig. 4). The wall and septal trabeculae quite 



distinct — exact conditions, however, disguised by the iiregularity of the skeleton. 

 P. Curagoa i'. See text, p. 31. 

 /'. Barbados f' (PI. I. fig. 8), with the wall and septal granules distinct, the latter 



tend to be united into a ring. 

 /*. Barbados o (PI. I. fig. 9). The wall and septal granules distinct where the 



elements are thin, but the two become confused when the elements are thick 



and run together. 

 P. Antiijaa 1 (I'l. II. fig. 4). The wall and septal granules very close together. 

 P. Antigua 2 (PI. II. fig. 5), with the wall trabeculse raised so as to make a thin 



castellated ring round the calicle. The intracaUcular skeleton somewhat 



confused. 

 P. Antigua 3 (PL II. fig. 6). The wall and septal granules frequently united into 



small petaloid flakes. The zigzag wall-thread frequently very thin. 

 P. Barhuda 1 (PL II. fig. 8). The septal gi-anules distinct, wherever skeleton is not 



all melted together (? by post-mortem aqueous corrosion). 

 P. Anguilla 1 (PI. III. fig. 2). The wall and septal trabeculae fairly distinct, but 



the calicle is very small, and the skeletal elements are thick and coarse ; the 



details are only discoverable with a lens. 

 P. St. Thomas 3 (PL III. fig. 4). The skeleton is open, with finely echinulate 



elements. The trabeculae are only just indicated by slight thickenings in the 



tracery. It appears as if the septal granules and the wall granules were 



distinct, though the details are confused by irregular echinulation. 

 P. St. Thomas 4 (I'L III. fig. .5). The three rings complete and distinct in larger 



calicles, but irregular and confused in the smaller. 

 /'. Florida ^ (PL III. fig. 8). The three circles distinct, the septal trabeculae and 



the wall trabeculic distinct, elements often smooth and sharply defined. 

 P. Florida 5 (PL III. fig. 9). The tliree ciicles distinct, but elements coarse, thick, 



and irregular. 

 P. Bermuda 1 (PL IV. fig. 7). The .skeleton here open, there with the walls and 



the septal granules tending to run into horizontal flakes. 

 I'. Bermuda J (PL IV. fig. 8). The points wliere the trabeculaj come to the surface 



confu.sed by echinulation, so tliat the smooth surface of wall and septal edges 



wliich look like narrow flak(!s have .saw-like edges. From the sizes of the 



calicles and the length of the septa, we may conclude that the tiiree circles are 



complete and distinct. 



