BY THE EEV. J. E. TEXISOX- WOODS, F.G.S., F.L.S., ETC. 46l 



synapticiila3 are few and quite at tlie base. The primaries are 

 quite free with a conspicuous thickening at their origin ; the 

 secondaries are also free with a slight thickening, and both have 

 a rounded crenulate margin. All the other orders gradually 

 branch out or divaricate from one another with a gradual curve. 

 They are very incompletely formed so as to be deeply divided 

 into irregular paliform lobes. The height to which the septa 

 rise is also dependant on their age, the first being much higher 

 than the rest and sloping gradually from the margin upwards 

 towards the central fossa and so on proportionately for all the 

 cycles. All except the central septum curve towards the outer 

 margin so as to preserve a flabellate form. In the fossa there 

 are a few papilla3 of a columella. 



There can be no doubt that this form of coral is a form of 

 Cycloseris, in which some of the systems are aborted. In this 

 view there is nothing to distinguish the x^resent species from C. 

 cijdolites, except the size. I do not say that this is the true 

 nature of the organism, but a close attention to the young stages 

 will reveal the whole matter. It will be observed that one strong 

 point in favour of the explanation which is suggested for this 

 abnormal coral is the variation in the number of systems which 

 are aborted. In many instances all are gone but one. In this 

 case however, we have a semicircular fringe of septa round the 

 fossa which represents all the other systems. Another fact is the 

 occurrence of one or two specimens in which only one system is 

 aborted. In this case the coral is to all intents and purposes a 

 very small and depressed C. cydolites minus one system. 



About sixty specimens were dredged up oif Holborn Island. 

 They are of various sizes and seem to indicate some disadvantageous 

 circumstances in their growth by which they have been stunted. 

 Some of the sx^ecimens were much eroded and full of small grains 

 of sand, foraminif era, &c. I have dedicated the species provision- 

 ally to Mr. Alexander Morton. 



