ON: FOSSIL POLYZOA. 173 
It is impossible under present circumstances, and with the poor 
material at my disposal, to work out the Cretaceous Membranipora. I 
will therefore give short notes of the species that have come under my 
own observation, in the hope that better materials will be forthcoming. 
Memeranrpora ROEMERI. 
? Marginaria Roemeri, Lonsdale, Dixon’s ‘ Sussex.’ 
This species is generally met with in small patches, and the cells are 
occasionally elongate and compressed towards the proximal extremity, at 
other times compressed so as to appear like the cells of M. angulosa. 
Reuss. 
Orifice of the cell semicircular, area depressed. 
Locality.—Upper Chalk, Sussex. 
In Miss Jelly’s collection there is a small specimen marked Marginaria, 
but it does not appear to me to be a young colony of M. Roemeri. There 
is in the specimens the same semicircular mouth, but the front of the cell 
is raised not depressed, and smaller cells of the same character intervene 
between the larger. 
MEMBRANIPORA INELEGANS. 
Flustra ? inelegans, Lonsdale, Dixon’s ‘ Sussex.’ 
This species is found in large and small patches. In the general 
arrangement and character of the cells this seems to remind one of the 
recent M. Lacroizii, Audouin. The Cretaceous fossil is much more com- 
pressed in the colonial growth than I have ever seen in the recent species, 
but none of the areas of the cells are like M. Savartii, Aud., which Mr. 
Busk (‘ Crag Polyzoa,’ p. 31) identifies with M. Lacroixi. 
Locality.—Upper Chalk, Sussex. 
MEMBRANIPORA sp. 
? Allied to M. Hookeri, J. Haime. 
Prof. Reuss, in his ‘ Alpine Tertiary Polyzoa,’ figures a specimen of 
M. Hookeri which resembles so closely the Cretaceous specimen before 
me, that I can hardly assign to it any other name. There is a larger 
colonial growth in the Cretaceous specimen than in any of the Tertiary 
specimens in my possession, and the walls are thicker; in other respects 
the resemblance between the Cretaceous and the Eocene species is 
remarkably close. With some little doubt, however, I place it as an 
allied form, rather than give to it a new name. 
Locality— Upper Chalk, Sussex (Miss Jelly). 
Genus CrIBRILINA, Gray. 
* Zoarium encrusting. Zoccia contiguous, having the front more or 
less occupied with transverse or radiating punctured furrows ; orifice 
semicircular or suborbicular.’—‘ Brit. Mar. Polyzoa,’ p. 184. 
CRIBRILINA RADIATA, Moll. 
For references, &c., see Hincks (loc. cit. pp. 185, 190). 
I have no record of this species oceurring in our British Cretaceous 
rocks. The forms are incrusting on fragments of Echinodermata from 
