ON THE SOLITARY CORALS, COLLECTED BY DR A. WILLEY. 177 



Fig. G. Lithophyllia palata,. n. sp. 



(a) Profile view of the corallum (x 2). The base and sides of the corallura are 

 much overgrown by an incrusting nullipore, some of the branches of which can be seen 

 to the left. In consequence of this the costae are, on the side shown in the figure, 

 inconspicuous. The primary septa are much larger and more exsert than the others, and in 

 front of four of them straight, paliform lobes can be seen. 



(b) The calice from above (x 2). Owing probably to the irregularity of the calice, 

 paliform lobes are only found in front of four of the primary septa instead of the whole 

 six as normal. The first three cycles of septa are complete ; the quaternaries are nearly 

 so, and in some of the systems septa of a quinary cycle are found. 



Fig. 7. Tridaeophyllia primordialis, n. sp. 



(a) Profile view of the youngest corallum (x 2). The two vertical branches are 

 commencing to grow out, and the costae are in this stage especially well marked. At the 

 base a small worm-tube is attached, 



(b) Profile view of another young corallum (x 2), in which one of the vertical 

 branches is much longer than the othi r. 



(c, d and e). Profile views of older coralla (c and d x 2, ex 3), showing variations 

 in the mode of growth. Four cycles of septa are present, of which the six primaries 

 extend one to the ends of each of the horizontal, and two to the sides of each of the 

 vertical branches. The corallum (e) is partially covered at its base by an incrusting 

 Polyzoon. 



Fig. S. Thecojisn hi miii retjularis, n. sp. 



(a) Profile view of the corallum (x 3), showing the high extension of the epitheca, 

 above which is seen the theca with its perforations in lines between the septa. No costae 

 are present. 



(6) The calice from above (x 6). The first two cycles of septa are complete and 

 fuse with the columella, which is formed of twisted lamellae. The tertiaries are likewise 

 complete and there are at least two quaternaries in each system on opposite sides of one 

 of the tertiaries. (The bluntly lobed character of the septal edges is not clearly shown.) 



Fig. 9. Balantyphyllia prqfundicdla, n. sp. 



(a) Profile view of the corallum (x 2i). The costae are subequal and well marked, 



the theca being little perforated between. The lower part of the corallum is much over- 

 grown by calcareous organisms and there is no epitheca. 



(6) The same from above (x 5). Three cycles of septa are complete and the fourth 



nearly so. The quaternaries fuse over the tertiaries and again over the secondaries, joining 



then deep down in the calice with the primaries so as to close the axial fossa below. 



Figs. 10—24. Various stages in the postembryonic development of Cycloseris hexagonalis, 

 Milne-Edwards and Haime. 



Fig. 10. Oral view of a young trophozooid (x 25) with seven septa, of which six are 

 much broader and fuse below with the columella. The edge of the corallum appears 

 smooth and slightly bent inwards owing to incrusting organisms growing over its sides. 



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