Mr. P. M'Coy on some new Mesozoic Radiata. 403 



4th into another, has retained the name Anthophyllum for the re- 

 mainder (Caryophylliafastigiata, &c), while, as above mentioned, 

 nearly all the continental palaeontologists have been in the habit 

 of using it for the very different, turbinated corals which now oc- 

 cupy us, and which agree with the general definition of Schweig- 

 ger, though probably not contemplated by him at the time. In 

 the young state those corals are attached by a broad base, which 

 soon becomes carious and hollow as the coral grows, undermi- 

 ning its base even to the thin external wall, which at last gives 

 way, and the corallum thus becomes a free cone with a naked, 

 obtusely rounded apex : some species grow so little vertically, that 

 the separation from the carious hollow old base is effected in a 

 nearly horizontal plane, so that the adult free corallum is scarcely 

 distinguishable from Cyclolites, being circular, thin, flat, the up- 

 per and lower surfaces nearly parallel and both radiated : whether 

 the form be flat or conical, the terminal star is never excavated 

 into a cup, by which the species may be known from Turbinolia 

 and Cyathina, as well as by the obtuseness of the margin (the 

 lamellae extending over it), the thin easily lost outer wall, and 

 the lamellae being very thick and simply meeting in the centre 

 without a cellulose axis. 



Montlivaultia gregaria (M'Coy). 



Sp. Char. Corallum forming turbinate masses (about 3 inches 

 wide and nearly 2 inches high) of few individuals which ter- 

 minate on the upper surface as prominent, disconnected, cir- 

 cular, slightly concave or convex discs with obtusely rounded 

 margins, generally l£ inch in diameter, with about eighty 

 thick radiating lamellae, many of which reach the centre, the 

 rest being irregularly smaller ; connecting vesicular plates very 

 delicate j external wall covering the lamellae very thin, rarely 

 preserved. 



The individuals of which the turbinate masses are composed 

 are identical in generic character with the ordinary Montlivaultice, 

 as the term is here used ; but no other species that I know has 

 this gregarious mode of growth, nor will any other genus con- 

 tain the species. 



Common in the inferior oolite of Dundry and Cheltenham. 



(Col. University of Cambridge.) 



Dendrophyllia plicata (M'Coy). 



Sp. Char. Corallum of approximately straight stems from 1| to 

 2 lines in diameter, giving off at an angle of about 60° branch- 

 like cells averaging 3 lines long and slightly less in diameter 

 than the stem, arranged spirally at short irregular distances ; 



28* 



