1882.]. CORALS FROM MADEIRA. 215 



Both these specimens came from oflf the same shell. 



A smaller individual of this species presents the peculiar ornamen- 

 tation of the costse near the calice and the shining epitheca. It is 

 cylindrical in shape, and is just beginning to curve at the top ; and 

 it is fixed, by a base with two small offshoots, within the hollow of 

 the valve of a shell. The calice is widely open, but has sharp 

 margins and very slender and somewhat exsert and tolerably bent 

 primary and secondary septa. 



The primaries and secondaries are nearly equal; the tertiaries are 

 much smaller; and the fourth and fifth orders of the fourth cycle of 

 septa are very small. The larger septa are wavy within, very slender, 

 and well separated. 



The columella occupies considerable space, and is composed of 

 about eight twisted band-like lamellae, which are separate. 



The pali are very small, and closely resemble the trabeculse of the 

 collumella ; but their union low down with the septa can sometimes 

 be seen. They are before the second and third orders of septa. 

 The corallum is excessively slender and transparent. 



Height of the coral -^^ inch. 



At the base of the specimen just described, and within the same 

 valve of a shell, is a very minute coral, which appears to be a still 

 smaller form of Caryophyllia cyathus. It has a circular calice, six 

 primary and six smaller or secondary septa ; and there are twelve 

 very small rudiments of the tertiary cycle. The larger septa are 

 slightly enlarged at their inner ends; and there are no pah, the 

 columellary trabeculae being very small and apparently in one little 

 bundle. 



It is evident from the study of these specimens that the peculiar 

 shining costal covering which has been termed a pellicular epitheca, 

 but which does not appear to be a true outer thecal covering, is 

 always present. The thickness of tlie septa and their crowded 

 state seen in the adults is a matter of growth ; and it is clear that 

 the first stage of the coral shows three cycles of septa, the tertiary 

 being rudimentary, and that in a more advanced stage there are four 

 perfect cycles. The full number of septa is obtained during adult 

 age ; and the whole of the calcareous tissues increase then in thick- 

 ness. 



In examining some pieces of worn coral, probably originally form- 

 ing part of a large Bendrophyllia, I found a small Caryophyllia cya- 

 thus. It has the peculiar epitheca, and is just in advance of the 

 smallest specimen just noticed, so far as its growth is concerned. 



There are four cycles of septa in some of the systems, and in the 

 others only three. The columella is a twisted piece of tissue ; and 

 the pali are small but distinct and are before the secondaries. 



Hence the coral with three cycles of septa in its early stage has 

 no pali ; they appear before the secondaries a little later, and subse- 

 quently before the tertiary ; and this takes place when the fourth 

 and fifth orders of septa are complete in a system. Then pali are 

 developed before a higher order and eighteen result. The pali are 

 deep in the calice, but project upwards ; and they send processes 



