Dr. G. J. Hinde on Fossil Calcispongie. 203 
forms can no longer be disputed, and that Prof. Zittel was 
fully justified in placing together as a distinct family of Calci- 
sponges the numerous sponges with structures similar to the 
above species. 
An examination of some of the calcareous sponges from 
Farringdon and Upware convinces me that they possess 
essentially similar minute structures to the sponges from 
Warminster and Vaches Noires, though, as a rule, their con- 
dition of preservation is unfavourable, and in no instance have 
dermal surface-spicules been detected; but thin sections of 
the fibres display similar features. For example, Corynella 
(Scyphia) foraminosa, Goldf., sp. (Petref. p. 86, t. 21. f. 4), 
from Farringdon, has the fibre made up of minute filiform 
spicules, apparently similar to those of C. rugosa. ‘The fibre 
also of the common Pharetrospongia (Manon) farringdo- 
nensis, Sharpe, sp. (Quart. Journ. Geol. Soe. vol. x. p. 196, 
t. 5. figs. 5, 6), is similarly of filiform spicules; but whether 
these are really uniaxal or triradiates with the minute basal. 
ray like those of Corynella rugosa, I have not yet been able to 
determine. ‘The fibre of Elasmostoma (Manon) macropora, 
Sharpe (Quart. Journ. Gol. Soc. vol. x. p. 195, t. 5. figs. 3, 
4), has a spicular structure of tri- and quadriradiates of the 
same character and arrangement as in Sestrostomella rugosa. 
Prof. Sollas has made this form the type of a new family and 
genus of siliceous sponges (Ann. & Mag. Nat. Hist. 1878, 
vol. 1. p. 336, fig. 1), on the supposed resemblance of the 
spicules to those of siliceous monactinellid and tetractinellid 
sponges, without apparently taking into account, amongst 
other things, the very great difference of size between the 
calcareous and siliceous forms, which of itself is sufficient to 
throw great doubt on their probable affinities. I have not 
been able to obtain a microscopic section of Verticillites ana- 
stomans, Mantell, sp. ‘ Medals of Creation,’ vol. i. p. 227, 
fig. 4), but entertain no doubt that its minute structure 
will be found to correspond with the closely allied V. D’ Or- 
bignyt. 
Not only in Cretaceous Calcisponges, but also in Jurassic 
examples, I am able to affirm the presence of a dermal layer 
of quadriradiate (?) spicules similar to those of the species 
above described. ‘Thus in Hudea perforata, Quenst., sp. 
(Der Jura, p. 698, t. 84. figs. 26, 27), from the Upper Jura 
of Nattheim, the summit of the sponge has a layer of these 
spicules, though they are not to be detected in the compact 
membrane (‘‘ Dermalschicht”’ of Zittel) which invests the sides 
of this species; they are also present on the summit of Husv- 
phonella Bronni, Goldf. (Petref. p. 91, t. 33. fig. 9), from the 
14* 
