BRITISH PAL^OGENE BEYOZOA. i^59 



English Eocenes. Among the species which M. Jullien [No. 2, p. 501, pi. xvii. figs. 72, 

 73] has referred to his genus Tervia it most resembles Tervia solidida. 



Species 4. iDMOisrEA coronopus, Defrance, 1821. 



Syn. Idmonea coronopus, Defrance, 1821, Diet, Sci. Nat. t. xsii. p. 565 (non Atlas, pi. xlvi. fig. 2, as 

 stated by Bronn) ; Blainville, 1830, ibid. t. Ix. p. 385 ; id. 1834, Man. d'Actinol. p. 420 ; 

 Milne-Edwards, 1836, in Lamarck, Anim. sans Vert. ed. 2, t. ii. pp. 281, 282 ; id. 1838, 

 Mem. Crisiees, Ann. Sci. Nat. Zool. ser. 2, t. ix. pp. 215, 216, pi. xii. fig. 3; Miclielin, 

 1844, Icon. Zooph. p. 172, pi. xlvi. fig. 16; Bronn, 1848, Index Palseont. Nomencl. p. 606 ; 

 Lonsdale, 1850, in Dixon, Geol. Sussex, pp. 153-155, pi. ix. fig. 24 ; Hagenow, 1851, Bryoz. 

 Maastr. Kreidebild. p. 25 ; Lonsdale, 1878, in Dixon, Geol. Sussex, ed. 2, pp. 204-206, 

 pi. ix. [10] fig. 24; Harris and Burrows, 1891, Eoc. and Oligoc. Paris Basin, p. 61. 



Retepora trigona, Morren, 1828, Desc. Corall. foss. Belgio, Ann. Gron. p. 37, pi. x. figs. 1-3 

 (identification fide Micbelin) ; Galeotti, 1838, Mem. Geogn. Brabant, p. 187, pi. iv. fig. 13 ; 

 Nyst, 1844, Coq. et Polyp, foss. Terr. Tert. Belg., Mem. Cour. R. Ac. Belg. t. xvii. 

 pp. 619, 620. 



Chrysisi7ia coronopus, Mourlon, 1881, Geol. Belgique, t. ii. p. 180. 



Hornera fl,abelliformis, Vine (non Blainv.), Proc. Yorks. Geol. & Polyt. Soc. vol. xi. p. 166, 

 pi. V. fig. 15 ; id. ibid. vol. xii. p. 53. 



Diagnosis. Zoarium small, erect, rising from an encrusting, expanded base. The 

 branches fork several times ; they are triangular in section and well rounded behind ; 

 they end bluntly. 



Zooecia in short transverse series, alternately arranged. The zocecia are single at the 

 base, but rapidly increase to rows of four ; this decreases to three above. The inner- 

 most zooecia are the longest. 



Peristome even, usually oblong with rounded angles ; younger and isolated zooecia 

 have oval or even circular apertures. 



Wall granular. 



Distribution. British: Bracklesham Beds, Bracklesham (Brit. Mus., Dixon and 

 Vine Collections). — Foreign : Calcaire grossier, Parnes, Grignon, Chaumont, &c. ; 

 Laekenien ; Uccle (near Brussels), de Foret, d'Assche. 



Figures. PL XXXII. figs. 6 a, 6 5. 



Affinities and Differences. As this species belongs to the typical group of Idmonea it 

 clearly differs from Idmonea [Tervia) seriatopora, Reuss. As there is uo median line 

 of zocecia it differs from Idmonea gieheli, Stol. From the third British Eocene species 

 it may readily be distinguished, as in that the zooecia are always in alternate pairs. 



Genus Hornera, Lamouroux, 1821. 

 [Lamouroux, No. 2, p. 41.] 

 Diagnosis. Pergens, 1889, No. 3, p. .353. 



Type species. Hornera frondiculata (Lamarck), 1816, No. i, pp. 182, 183. 

 VOL. XIII. — PART VI. No. 6. — June, 1893. 2 p 



