252 MB. J. W. GREGORY ON THE 



Species 1. Conescharellina clithridiata, n. sp. 



Syn. Cellepora, sp.j Wetherell, 1837, Trans. Geol. Soc. ser. 2, vol. v. pi. is. fig. 21 ; Busk, 1866, 

 Geol. Mag. vol. iii. p. 301. 

 Cellepora sp. (pumicosa?), Vine, 1890, Proc. Yorks. Geol. & Polyt. Soc. xi. p. 164. 



Diagnosis. Zoarium a small, thick, globular mass ; base contracted (1 attached). 



Zocecia few in number and irregularly distributed and not arranged around a central 

 cell. The apertures of the zocecia are clithridi ate in shape; they are large and terminal. 

 The zocecia are tumid and generally hexagonal in outline ; the front walls are granular 

 and steep ; the zocecia are separated by deep depressions. 



Ocecia very large in proportion to the size of the zocecia ; globose, tumid, overhanging 

 the aperture. Only rare zoaria show them, but then they are numerous. 



Distribution. London Clay : Highgate, Sydenham, &c. 



Type. Brit. Mus. No. B 1357 (Wetherell's specimen. No. 69554). 



Dimensions. The largest zoarium is 1 mm. in diameter. 



Figures. PI. XXXI. fig. 10. A zoarium from the London Clay, Hampstead ; Brit. 

 Mus. No. 69554. — Fig. 11. A zoarium from Sj'denham with ocecia. 



Affinities. A charming little figure of a specimen of this species has been given by 

 Wetherell. The species, however, was not named and it has been missed by all subse- 

 quent workers. His specimen is in the British Museum collection, along with a great 

 number from the London Clay at Sydenham. This species belongs to the group of 

 which Cellepora glohularis, Bronn [No. 2, p. 654], was the first described species ; as 

 Reuss [No. 9, pp. 113, 114] has, however, pointed out, several distinct forms have come 

 in time to be included under this name. The specimen recently figured by Gioli 

 [No. I, pp. 263, 264, pi. xiv. fig. 9] appears to be quite distinct. Pergens's short 

 synonymy [No. 4, p. xvi] shows much discrimination. 



The nearest ally of this species, C. scrohiculata (Koschinsky) [No. i, p. 63, pi. vi. 

 figs. 2, 3], has a hemispherical or conical zoarium, the base being expanded instead of 

 contracted as in all the English specimens ; the aperture in the Bavarian species is also 

 circular and surrounded by a rim. The new species difi'ers from C. multiradiata, Reuss 

 [No. II, p. 265, pi. xxxi. figs. 1-4, and Waters, No. 12, pp. 32, 33], as in that the 

 zocecia are barrel-shaped, the apertures flush with the surface of the zoarium, and it is 

 composed of several layers; the ooecia also are much larger. From the Miocene 

 Conescharellina rosula (Reuss) [No. i, p. 78, pi. ix. fig. 17, and Manzoni, No. 3, p. 54, 

 pi. ii. fig. 6] the London species difi'ers in its clithridiate aperture and the less elevated 

 zocecia. The same characters also separate it from G. stoliczkai (Reuss) [No. 10, 

 pp. 223-226, pi. ii. figs. 2-4]. 



In agreement with the zoologists I accept the name Conescharellina in preference to 

 Reuss's Batopora, which has been adopted by most palaeontologists. There seems 

 little room for doubt as to the identity of the two. D'Orbigny's genus was diagnosed 



