114 CARBONIFEROUS CORALS AND BRACHIOPODS 
is associated with every variety of external aspect and 
calyx, renders a specific separation based on this character 
utterly impossible. 
The reasons for separating the short everted forms will 
be given under Cyatliophyllum regium (v.i.). 
The specimens in the Stoddart collection are very 
numerous, the greater number being polished sections, 
both horizontal and vertical. Amongst the uncut speci- 
mens there are examples of most of the common varieties, 
some of whieh show a fiat calicinal floor, others a eentral 
elevation with a shallow depression on top and a deep 
fossula, whilst some show the elevation and fossula but 
no inner depression. The horizontal sections show every 
variation in the thickness of the septa and in the relative 
extent of the singly- septate area. The vertical sections 
are particularly interesting as showing the variability of 
the central structure and its independence of other 
characters. One such section, which is perfectly axial 
throughout its extent, is cut from a specimen exhibiting 
the characteristic close rings on its external surface and a 
calyx whose floor is perfectly flat. The central portion of 
this section, in its upper part for some distance below the 
floor of the calyx, is composed of very close tabulae nearly 
12 mm. in breadth, but this structure is succeeded lower 
down by the normal vesicular type in which short tabulae, 
scarcely 2 mm, broad, occur at vertical intervals of about 
6J 'mm., and are separated by broad zones composed of 
row upon row of fine vesicles. 
All the specimens are derived from the upper portion of 
the Carboniferous Limestone and chiefly from near the 
Point. 
Cyathoyhyllum regium, Phill. (= Astroe.a carhonaria, 
McCoy). 
This species has been considered by Edwards and 
