VINE : POLYZOA OF THE LOWER AND UPPER GREENSAND. 263 
tapering towards the proximal extremity, occasionally bulging and 
contracted towards the distal, surface faintly punctate, orifice rather 
less than the breadth of the cell, peristome raised. 
Length : 4 cells measure slightly over a quarter of an inch. 
Breadth : Less than 1 mm. 
Habitat : On the inner portion, and outer lip of Radiolites 
Mortoni, Mant. 
Horizon : Cambridge Greensand. 
S. linearis, D'Orb. Loc. : Havre. Cenomanien. Etage 20e. 
This beautiful variety I have named Mortoni, on account of its 
peculiar habitat, but another small fragment (figs. Ic and Id) was 
found in the inner portion of a dead ostrea, likewise attached to 
Radiolites Mortoni. The two forms appear to be identical. ^ On the 
outer lip of the same fossil was a very large colony of Memhranipora 
Dumerilla, Aud., var. Cantahrigiensis, Vine, as well as colonies of 
Diastopora. 
11. Stomatophora graciliformis" (D'Orb. sp.), pi. xii., figs. 2 to 2b. 
1848. = Stomatophora gracilis, Bronn (D'Orb.), Terr. Cret., p. 843. 
1850. = Alecto gracilis, D'Orb., Terr. Cret. ibid, pi. 629, figs. 1-4. 
This species, so far as I am" acquainted with it, is always small 
or delicate, and very distinct. The Zoarium branches frequently, 
almost every cell, or at most two cells, branch off irregularly. The 
Zooecia are slightly rugose, short, but occasionally 1 mm. in length, 
and tapering towards the proximal extremity. The general habit of 
the species more closely resembles the Alecto gracilis, D'Orb., than 
any other that I am acquainted with. ^ 
Habitat f On the smaller examples of Radiolites Mm^toni Mant. 
Horizon : Cambridge Greensand. 
D'Orbiguy's >S'. gracilis is from Meudon, in Senonien Rocks. 
Etage 22e. 
12. Proboscina dilatata, D'Orb. 
1850. Idmo7iea dilatata, D'Orb. Tert. Cret., t. v., p. 851, pi. 632, 
figs. 4-6. 
Var. cantahrigiensis, var. n. pi. xii., figs. 3-3a, 4-4a. 
Zoarium adherent, ramified, originating from a short stem from 
* I have adopted this name lo keep the species distinct from that of M. Edwards. 
