R. F. Tomes — Some Cretaceous Madrejjoraria. 549 



So far as I have been able to observe, there is no true wall, only- 

 such a one as vpould be formed by the union of synapticulae near 

 the outside of the corallum. Beyond tliis so-formed wall the ends of 

 the septa project, and unless hidden beneath bands of irregularly 

 developed pellicular epitheca, synapticulge may be seen between 

 them. 



I am not at present familiar with the endotheca of any species of 

 Mhizangia, excepting the species here mentioned, and am indeed 

 prepared to learn that it has not yet received attention at the hands 

 of zoophytologists. So far, however, as may be gathered from an 

 inspection of the figures of some of the species, there are indications 

 of a septal structure corresponding with what I have above described. 

 The denticulations of the septa of such species as Rhizangia procurrens, 

 Eeuss,^ bear but little resemblance to those of any of the Astrceidcs. 

 They more neai'ly correspond with the denticulations of the septa of 

 some of the FimgidcB, and are probably the terminations of vertical 

 trabiculas, loaded by a synapticular growth, as in Cyclolites and 

 Leptophyllia. 



To the genus Podoseris, first formed for the reception of these 

 Red-Chalk corals, another species from the Inferior Oolite of Dorset- 

 shire has been added by Professor Duncan. This is Podoseris 

 constricta, the type of which has lately been in my hands. The 

 examination of it and of some other corals from the same bed has 

 convinced me that it is nothing more than an abnormal form of a 

 species appertaining to an old and well-known genus. 



The genus Syzygophyllum of Reuss appears to me to possess some 

 characters which are not wholly inconsistent with those of Rhizangia.^ 

 The figures of Syzygophyllum brevis are by no means unlike many 

 specimens of Rhizangia elongata, and the description given by Ruess 

 supplies some particulars which are equally consistent with it. The 

 broadly-attached corallum, the moderately-developed columella with 

 its papillated upper surface, the anastomozing septa, and the toothed 

 mural costee (when not obscured by epitheca) sufficiently illustrate 

 this. The lateral ornamentation of the septa, and the endotheca, 

 appear, however, to differ materially. The following is a translation 

 of the words used by Ruess : — "The lateral surfaces of the septa ai-e 

 united by numerous thin, very flat, bow-shaped, endothecal lamellae, 

 which form a large vesicular mesh- work. Together with them they 

 bear scattered gi'anular pimples. In a ci'oss-section of the corallum 

 the endothecal vesicles are observed forraingpretty regular concentric 

 rows." I may call attention to the ornamentation of the septa shown 

 in the magnified figure (Fig. Sb), and suggest that the genus 

 Syzygophyllum is one which demands further investigation. 



Although I have myself collected corals from the cliff at 

 Hunstanton, I am unable to speak of their precise position in it. 

 That deficiency has, however, been fully made up by Professor T. 

 Wiltshire, who has taken Rhizangia mamilliformis from the top 



^ Foss. Korall d. Osterreichisch-Ungarischen Miocans, Taf. vi. fig. 1. 



^ Foss. Korall des Osterreichisuh-Ungarischeu Miocans, p. 36. Taf. v. figs. 6-9. 



