A monograph of the British fossil corals - kreidefossilien.de

CORALS FROM THE LOWER CHALK. 55
the fifth order being rather longer than those of the fourth order. The septa of the fifth
cyclum are small, thin, low, and unite to the neighbouring principal septa ; those of the
sixth order join the primary ones ; those of the seventh order adhere by their inner and
upper edge to the secondary ones, and those of
the eighth and ninth orders to the tertiary
septa ; or, in other words, each element of this fifth cyclum joins the eldest of the two
septa between which it is placed. Lidependently of these junctions, which are normal, and
always take place along the inner edge of the septa, the interseptal loculi are irregularly
divided in some places by the projecting lateral granute of two neighbouring septa
meeting, and becoming cemented together. By this character, as well as by its general
form, this species tends to unite the family of Eupsammidse with the Fungidse.
Height of the corallum, one and a half or two lines ; diameter, three or four lines.
Some specimens, which were probably not adult, were only two lines and a half in
diameter.
This delicate little Coral differs from Stephanophyllia elegans, S. imperialis, and
S. discoides^ by the form of the septa, which do not appear to be angular and lacerated,
as in the three latter species. Stej}kanojj/ij/Uia astreata" differs fi'om it by having a large
fossula and a well-developed columella.
It most resembles 8. stiecica / but in this species
the two tertiary septa of each system unite below the columella and the secondary septa,
which consequently do not extend to the centre of the calice ; whereas in 8. Bowerbankii
these tertiary septa, as we have ah'eady stated, adhere to the secondary septa, and these
last-mentioned septa extend to the columella. The Fossil Coral figm'ed by M. von
Hageuow, under the name of Ftmgia clathrata* and found by that geologist in the chalk
formation of Rugen, is evidently very nearly allied to the British species here described ;
but as far as we can judge of it by M. von Hagenow's engraving, it appears to differ from
it by its more elevated form, by the strongly-marked concentric striae visible on the mural
disc, and by its basis being more prominent.
We must also remark, that the section of the genus Stephanophyllia, to which this
species belongs, and to which we applied the name of Lenticular 8tephanophylUa^ has of
1 See our Monograph of the Eupsammidse, Ann. des So. Nat., S""" serie, vol. x.
2 Fimgia astreata, Goldfuss, Petref. Germ., vol. i, p. 47, tab. xiv, fig. 1 (where it is by mistake
designated under the name of Fungia radiata). This species not having been, as yet, well characterised,
we think it may be useful to give a short description of it here. Corallum simple, very short, and having
the form of a plano-convex lens. Calicular fossula circular, and well developed. Costfe very delicate
and not closely set. Septa forming five complete cycla, and appearing to be thin and strongly granulated.
Size very variable ; in the adult, diameter three lines, height about one line. Fossil found at Aix-la-Chapelle,
in Westphalia, and existing in the Museums of Bonn and Paris. All the specimens yet found are in a very
bad state of preservation.
* Monogr. of the Eupsammidae, loc. cit., p. 94.
•*
In Leonhard and Bronn's Jahrbuch fiir Mineralogie, 1840, p. 684, tab. ix, fig. 3.
5 Monogr. of the Eupsammidse, loc. cit., p. 94, 1848.