OF THE MEEGUI AECHIPELAGO. 



11 



Goxiastbj:a halicoea. 



Astraea halicora, Hemp, Ehr. Abhandl. Akad. Berl. 1832, p. 321. 

 Prionastraea halicora, Ed. 8f H. Hist. Nat. des Corall. t. ii. p. 517- 

 Goniastraea halicora, Klunz. op. cit. pt. iii. p. 33, Taf. iv. fig. 1, & Taf. x. 

 fig. 3 a & b. 



Locality, King Island Bay. 



A variety. 



Locality, King Island Bay. 



0tO>~iastej:a i>*CErsTA>'s, sp. nov. (Plate I. figs. 19, 20.) 



The colony is large, swollen and gibbous above, and has a thin 

 edge, where an epitheca of a basal nature is seen. Encrusting 

 old corals and parts of dead individuals of the same species. 

 Calices very variable in shape and size, generally irregularly 

 hexagonal, often elongate, and some are more simple than hexa- 

 gonal, with a large crown of pali. Shallow as a rule, but many 

 are deep ; united to the neighbouring corallites by sharp ridges 

 at the surface or by decidedly broad ones ; in some parts there 

 is a delicate line or furrow on the broad ridge over which 

 the septa do not pass. Septa extremely variable in number, 

 but the complete fifth cycle is not present. The distinction 

 between the cycles is not possible, and the long and larger are 

 separated by smaller and shorter septa ; hence the arrangement is 

 alternate, and this is found in small calices as well as in large. 

 The septa are rather crowded, alternately large and small, and 

 project but slightly from the wall, are straight, and sharply 

 and minutely granular at the free edge. The pali form a very 

 large crown, and encircle a deep and small columellary space ; 

 they are before nearly all the longer septa, and are often broader 

 and higher than the septal ends, and are boldly arched and 

 minutely granular. As the septal number of neighbouring 

 calices is never the same, so the size of the crown of pali varies 

 greatly. In some large calices where there are forty-eight septa 

 the pali are before the large twenty- four septa, and then it may 

 occur that those opposite the tertiaries are smaller than the 

 others and bend towards them. But this arrangement does not 

 always occur. Size of the calices has not everything to do with 

 the dimensions of the crow r n of pali, for neighbouring calices 

 exist of the same size, and in one there are not so many septa as 

 the size would appear to warrant and the pali are diminished in 

 number. In some recently formed corallites the septa are 

 slender and there are no pali ; these occur near the margin of the 



