ii8 



Lastly, No. 3 is interesting, as showing the mode of growth 

 of the species. Six pali are present before the secondary septa, 

 while in the larger forms pali are only found before the tertiary 

 septa. This change must be brought about by the first six pali 

 fusing wdth their septa, and a fresh series forming opposite to 

 the tertiary septa,* a modification of the same condition ap- 

 parently producing the variation found in No. I. 



No. I approaches C. scobinosa and scyllaeomorpha in shape 

 and in the character of its costae, which are overlaid and filled 

 ir. by epitheca. They are distinct near the margin of the 

 calicle, primaries more prominent, but below in some parts are 

 not visible, as in scyllaeornorpha, and in others present char- 

 acters described for scobinosa. In one system the quaternary 

 septa may be more exsert than the tertiary as in scobinosa, but 

 in another the reverse is the case. Granular striae on the 

 septal sides, radiating from the theca and running perhaps into 

 Imes of spines, or small ridges, are common, so far as I have 

 seen, to the septa of all Caryophyllia, and represent the centres 

 of growth or deposition of the septa. The axial fossa in all 

 my specimens is relatively shallow, but varies in every individual 

 specimen. 



The arrangement of septa in Caryophyllia is essentially 

 hexaradiate. I have not enough specimens to see definitely 

 whether the species has typically four or five cycles of septa. 

 If, as I believe, four cycles is the adult number, No. 5 is a true 

 variation, but if five cycles, possibly only a stage of growth ; 

 the same remark applies also to scyllaeomorpha. 



Localities. — I., 85-90 fathoms, Cape St. Blaize, N. by E. \ N., 

 65 miles, rock. II., 80-100 fathoms, Cape Vidal, N.N.E. i N., 

 g\ miles, rock. III., 310 fathoms, Buffalo River, N., 15 miles, 

 coral and mud. 



Genus CERATOTROCHUS. 



13. CERATOTROCHUS JOHNSONI (Duncan. PI. I., 

 figs. 5 a-c, and PI. II., fig. M.) 



C. johnsoni, Duncan, Proc. Zool. Soc, 1882, p. 217, pi. VIII., 

 figs. 5-8. 



Locality. — I., six specimens, from 54 fathoms, Cape Natal, W. 

 by N., 6j miles, fine sand and algae. II., one specimen, from 

 45 fathoms, lat. 32° 53' S., long. 28° 18' E., coralline stuff. 



Seven specimens in the collection agree with Duncan's de- 

 scription in the absence of pali and any determinate epitheca, in 



* The same method of jjrowth is indicated in Duncan's account of C. cyathiis 

 (Proc. Zoo. Soc, 1882, p. 214). 



