CORALS FROM THE MOUNTAIN LIMESTONE. 169 



The British specimens of this species that we have seen in the Museum of Bristol and 

 of Practical Geology, were all younger than some of our Belgian specimens, and that 

 circumstance accounts for their not having so many septa, (twenty-six instead of thirty -two,) 

 their calice was also more or less broken down, the upper tabula appeared also more 

 extensive than in the well-preserved adult individuals; but not having discovered any 

 important difference between all these fossils we are confident in their specific identity. 



As the position and the form of the septal fossula appear to furnish very good characters 

 for the different species of this genus, Z. Phillipsi may at first sight be distinguished from 

 all the species in which that fossula is placed on the ventral or inverted side of the 

 corallum, and from those in which the fossula, although placed, as in this, on the dorsal 

 side, is quite near to the wall of the calice, and extends but little towards the centre of the 

 visceral chamber. The species in which the fossula so far resembles that of Z. Phillipsi 

 differ from it by the following peculiarities : in Z. cornucopia^ the fossula is long and 

 narrow ; in Z. Konincki" the septa are thicker towards their upper end and have a 

 prominent lobe at their inner edge ; in Z. Griffith? there are two small septal fossilise, and 

 in Z. Michelini* the general form of the corallum is less elongate and less regular, and the 

 septa are stronger and more equal in size. 



3. Zaphrentis Griffithi. Tab. XXXIV, figs. 3, 3a. 



Zaphrentis Griffithi, Milne Edwards and Jules Haime, Pol. Foss. des Terr. Palaeoz., 



p. 333, 1851. 



Corallum short, turbinate, and slightly curved. Epitheca thin, and forming small 

 circular ridges. Calice circular, not very deep, and having a thin edge. Septal fossula 

 large, deep, extending to the centre of the calice, and placed on the dorsal side of the 

 corallum, (that is to say, towards the convex curve.) Some appearance of two other small 

 septal fossulae placed at right angles with the former one. Thirty-six principal septa, 

 somewhat unequally developed alternately, not closely set, and uniting two by two at 

 their inner edge, where they are slightly bent ; those situated near the fossula are some- 

 what deviated from the normal radiate direction, and unite at their inner edge so as to 

 constitute the lateral margins of the fossula ; an equal number of small septa alternating 

 with those above described. Tabulae well developed. Height of the corallum 12 or 13 

 lines ; diameter of the calice somewhat more. 



The only specimen that we have seen belongs to the collection of Mr. Stokes, and was 

 found at Clifton. 



This species differs from all the other known Zaphrentes in having its septal fossula 

 centro-dorsal, two small lateral fossulae, and a short and broad form. 



1 Caninia cornucopice, Michelin, Icon., tab. lix, fig. 5 ; Milne Edwards and Jules Haime, Polyp. 

 Palseoz., tab. v, fig. 4. 2 Milne Edwards and Jules Haime, op. cit., tab. v, fig. 5. 



3 See tab. xxxiv, fig. 3. ' Ibid., op. cit., tab. iii, fig. 8. 



