ANIMALS. 43 



Phyllopora Ehrenbergi, Geinitz. PI. V, figs. 1, 2, 3, 4, 5, 6. 



GoRGONiA Ehrenbergi, Geiuitz. Grundriss, p. 585, pi. xxiii a, fig. 12, 1846. 

 Fenestella Permiana, King. Catalogue, p. 6, 1848. 

 Retepora Lonsdalii, Howse. T. N. F. C. vol. i, p. 263, 1848. 

 Fenestella Ehrenbergi, Geinitz. Versteiner., p. 18, pi. vii, figs. 16-18, 1848. 



Diagnosis. — Foliations infimdibuliform : generally (?) not much folded. Meshes 

 oval : a little wider than the interstices : in general arranged in linear series 

 longitudinally; and alternately in the opposite direction. Cellules slightly inclined 

 upwards : from two to three on an interstice : with an oval or circular aperture, and 

 a polygonal base. Non-celhdiferous face marked with fine, waved, longitudinal striae. 

 Capillary tubes flexuous. 



This beautiful Coral, first discovered by Geinitz, is remarkable for consisting 

 apparently/ of a single funnel-shaped foliation, strikingly conical when young (vide 

 PI. V, fig. 2), but afterwards becoming more expanded. Besides the figure just 

 referred to, Dr. Geinitz has given a similar one representing a specimen equally as 

 conical in form, and a larger one showing the same character ; and Mr. G. Tate 

 collected a beautiful specimen at Tunstall Hill, of a nearly cylindrical form, and in a 

 very unusual state of preservation, showing its inner or non-celluliferous surface. It 

 must not be omitted, however, that I suspect, when we are more acquainted with this 

 species, it will be found to consist of a number of foliations, as in the Fenestellidce 

 already described. Allusion has already been made to the nearly vertical position of 

 the cellules in relation to the plane of the foliations, a character so marked, that I have 

 been induced to regard it as of generic importance. Figure 6 of Plate V represents a 

 magnified view of the cellules ; showing how strikingly their position contrasts with the 

 curving and imbricated character of the cellules of Synocladia virgulacea. 



Phyllopora Ehrenhergi appears to be a scarce Coral both in England and Germany. 

 It occurs very rarely at Silksworth, Tunstall Hill, and Humbleton Quarry, in the 

 Magnesian Limestone. Geinitz mentions its occurrence in the Lower Zechstein at 

 Corbusen and Milbitz ; and in the Zechstein-Dolomite at Gliicksbrunn. 



Family Thamniscid^, King. 1849.^ 



This group comprises certain shrub-like genera of Palaeozoic ciliobrachiate Corals, 

 possessing the bi-structural and polypidomial characters of Fenestellidias, and having 

 very much the appearance of recent Horneras. It embraces the two following genera, 

 one of which {Thamniscus) is the type, and apparently Mr. M'Coy's Ichthyorachis. All 

 the known constituent genera are readily distinguished from Fenestellidias by having 

 free stems and branches. 



1 Annals and Magazine of Natural History, 2d series, vol. iii, p. 389. 



