1871.] MR. W. S. KENT ON NEW MADREPORES. 281 



pit-like interseptal chambers, as in the preceding species. Colu- 

 mella deeply immersed, cylindrical, echinate, its apex pointed. 

 Surface of the main stem and the origins of the branches delicate 

 rose-madder, the ultimate ramifications almost white. Length and 

 breadth of entire corallum of the single specimen examined three and 

 a half inches ; diameter of the main stem half an inch, of the 

 calices half a line. Ampullae rudimentary, in the form of minute 

 vesiculse, distributed among the calices throughout the branches, 

 though in greatest profusion towards their distal extremities. 



Hab. Unrecorded. Sir E. Belcher's Collection. B.M. 



The form referred to this genus as A. oculata by Dr. P. M. 

 Duncan, in his description of the ' Porcupine ' Expedition (Madre- 

 poraria, Proc. Roy. Soc, p. 295, 18/0), is a true Stylaster, closely 

 allied to S. gemmascens (M.-Edw.), Madrepora gemmascens, Esper 

 (Pflanzenthiere, t. i. pi. 55, 1797), inhabiting the Indian seas. The 

 gemmation in this species, though at first sight apparently irregular, 

 is, on close examination, found to exhibit the alternate distal terminal 

 gemmation and more or less attendant latero-linear arrangement of 

 the calices on the main branches characteristic of Stylaster. Some 

 time back Dr. Duncan kindly favoured me with a small specimen of 

 this interesting coral, and since then he has permitted me to exa- 

 mine the whole series collected ; but it being the property of the 

 above expedition, I leave it to him to furnish the name and specific 

 diagnosis. 



Comparison with the figures of A. oculata in the ' Annales des 

 Sciences Naturelles,' torn. xiii. pi. 4. fig. 4, 1850, shows that this 

 species possesses altogether different characters. 



DlSTICHOPORA ROSEA, n. Sp. 



Corallum arborescent, branches nearly cylindrical. Calices occu- 

 pying deep and occasionally irregularly interrupted lateral furrows ; 

 margins of the furrows very prominent. Columella attenuate, stylate, 

 echinate, very deeply immersed, made visible by fracture of the 

 corallum. Height of corallum one or two inches ; diameter of the 

 calicinal furrows 2 -L inch, of the branches 5 inch. Colour of the 

 ccenenchyma bright rose-pink. 



Hab. East coast of Australia. B.M. 



As already shown by Count de Pourtales, the structure of the 

 calices in Distichopora is identical with what obtains in Stylaster and 

 Allopora, with the exception that the calices are confluent. In this 

 respect Distichopora bears much the same relation to the two genera 

 just mentioned as Lithophyllia and Dasyphyllia do to Mussa and 

 Symphyllia among the Astreidse. In Distichopora isolated calices 

 are occasionally met with ; and it is then that their similarity to those 

 of other Stylasteracese become most apparent. I must differ with 

 Count de Pourtales in considering this genus to be more closely 

 allied, individually, to Stylaster than to Allopora, the latero-linear 

 disposition of the calices indicating their development from primary 

 alternate distal rather than from an irregularly scattered gem- 

 mation. 



