CORALS FROM THE SILURIAN FORMATION. 291 



5. Genus Chonophyllum (p. lxix). 



Chonophyllum perfoliatum ? Tab. LXVIII, figs. 2, 2a. (See p. 235, and Tab. IV, fig. 5.) 



It is not without some hesitation that we refer to this species, already described in 

 the preceding chapter as being common in the Devonian formation, a coral found by 

 M. D'Archiac in the Silurian rocks at Wenlock. The only apparent difference between 

 this fossil and the Torquay specimen consists in the form of the calice, the border of 

 which is not everted. 



6. Genus Ptychophyllum (p. lxix). 



Ptychophyllum patellatum. Tab. LXVII. figs. 4, 4«. 



Fungites mediae, &c, Magnus Bromel, Acta Liter. Suec, vol. ii, p. 463, 1728. 



— patellatus, Schlotheim, Petref., 1st part, p. 247, 1820. 



— — Kruger, Gesch. der Urwelt, vol. ii, p. 253, 1823. 



— — Hisinger, Leth. Suec, p. 99, pi. xxviii, fig. 3, 1837. 

 Stiiombodes plicatum, Lonsdale, in Murchison, Sil. Syst., p. 691, pi. xvi bis, fig. 4, 1839. 



— plicatus, M'Coy, Sil. Foss. of Ireland, p. 61, 1846. 

 Cyathophyllum patellatum, Bronn, Index Pal., vol. i, p. 369, 1848. 

 Cyathaxonia plicata, jyOrbigny, Prodr. de Pal., vol. i, p. 48, 1850. 

 Ptychophyllum patellatum, Milne Edwards and Jules Haime, Pol. Foss. des Terr. Palseoz. 



(Arch, du Mus., vol. v), p. 407, 1851. 



Corallum simple, pedicellated, straight or slightly curved, and short. Epitheca 

 wrinkled; borders of the calice lamellated and very much everted, so as to give to the corallum 

 the form of a mushroom, and to produce a circular elevation around the central fossula, 

 which is very deep. Pseudo-columella small. Septa nearly 100 in number, somewhat 

 unequally developed alternately, rather thick exteriorly, but very slender towards the centre 

 of the calice, where the large ones become strongly twisted, and rise up a little to form 

 the columella. Height about 1 \ inch ; diameter of the calice twice the height or even more. 



Brand Lodge, Malvern, Malvern Mountains. Doonquin and Dingle, in the county of 

 Kerry (M'Coy). It is also met with in Gothland. 



Specimens are in the Bristol Museum, Bonn Museum, in the Collections of the 

 Geological Society of London, and of M. de Verneuil. 



This species much resembles P. extensum 1 in its general form, but its septa are more 

 numerous and more equally developed. It differs from P. Stokesi? by the lesser size of 

 its pseudo-columella. 



1 Milne Edwards and Jules Haime, Pol. Foss. des Terr. Palseoz., p. 408, pi. viii, fig. 2. 



2 Ibid., p. 407; Stokes, Geol. Trans., 2d ser., vol. i, pi. xxix, fig. 1 (dextrd), 1824. 



