498 W. D. Lang — Cretaceous Cheilostome Polyzoa. 



Key to the genus Rhammatopora. 



A. Zocecia tapering somewhat distally as well as proximally; 



proximal end of capitulum bounded by well-curved lines 



1. R. Johns toniana (Mantell). 



B. Zocecia blunt distally and tapering proximally. 



1. Outline of proximal end of capitulum bounded by hardly- 



curved lines; aperture elliptical. 2. B. vinei, n.sp. 



2. Outline of proximal end of capitulum bounded by well- 



curved lines. 



a. Extra-terminal front wall small laterally ; aperture 



oval to ovate . . . 3. B. gaultina (Vine). 



b. Extra-terminal front wall well-developed laterally; 



aperture ovate to elliptical . 4. B. pembrokiae, n.sp. 



Rhamhatopoea johnstoniana (Mantell). 

 Synonymy. 



Crisia Johnstoniana; Mantell, 1844, "Medals of Creation," 1st edition, 

 p. 285, pi. lxiv, figs. 3, 10, and 106; and 1854, op. cit., 2nd edition, 

 p. 269, pi. lxxxix, figs. 3, 10, 10&. 

 non Hippothoa Johnstoni (Mant.) ; Morris, 1854, " A Catalogue of British 

 Fossils," 2nd edition, p. 125; Upper Chalk; Kent, Sussex. 

 [? = Herpetopora anglica] . 

 non = Membranipora dispersa, Hag.; as stated by Vine, 1893, " Beport 

 ... on Cretaceous Polyzoa," Bep. Brit. Assoc, Edinburgh, 1892, 

 p. 316. 

 Revised diagnosis. Rhammatopora in which the angle of branching 

 is small, 45° or less ; the zocecia taper somewhat distally as well as 

 proximally ; the capitulum is bounded proximally hy well-curved 

 lines ; and the aperture is elliptical. 



Distribution. Aptian, Lower Greensand, Shanklin Sand ; Maidstone, 

 Kent. 



Remarhs. Mantell's figures only are available for the interpretation 

 of this species, but the generic and specific characters can easily be 

 seen in them. The branching appears to be somewhat irregular ; 

 how far this was so can be settled only if the type is found. Compare 

 the similar case of the figured specimen of R. gaultina. 



Rhamhatopoea vinei, n.sp. PL XVII, fig. 1, 

 Synonymy. 

 Membranipora gaultina, sp. nov. ; Vine, 1890, Quart. Journ. Geol. Soc, 



vol. xlvi, pp. 484, 461, pi. xix, figs. IBa-d ; Bed Chalk ; Hunstanton. 

 non Membranipora gaultina, sp. nov. ; Vine, 1890, loc. cit. ; Gault ; 



Cambridge. [= Bhainmatopora gaultina (Vine) q.v.]. 

 non Membranipora gaultina, sp. nov. ; Vine, 1890, op. cit., p. 461 ; Chalk 



Marl. [Probably = Bhainmatopora pembrokiae, q.v.]. 

 Membranipora gaultina, Vine; Vine, 1891, Proc. Yorks. Geol. Poly. Soc, 



new series, vol. xi, part iii, pp. 385, 396 ; Bed Chalk, Hunstanton. 

 non Membranipora gaultina, Vine; Vine, 1891, loc. cit.; Gault; Cam- 

 bridge. [= Bhainmatopora gaultina (Vine), q.v.]. 

 Membranipora gaultina, var., Vine : Vine, 1891, Bep. Brit. Assoc, Leeds, 



1890, p. 395 ; Bed Chalk ; Hunstanton. 

 Membranipora gaultina, Vine ; Vine, 1892, Proc. Yorks. Geol. Poly. Soc, 



new series, vol. xii, part ii, p. 155 ; Bed Chalk ; Hunstanton. 

 non Membranipora gaultina, Vine; Vine, 1892, op. cit., pp. 154-5, pi. vi, 



fig. 15; Gault; Barnwell, Cambridge. [= Bhammatopora gaultina 



(Vine), q.v.]. 

 Membranipora gaultina, Vine ; Vine, 1893, Bep. Brit. Assoc, Edinburgh, 



1892, p. 335 ; Bed Chalk ; Hunstanton. 



