CKISIXA. 
183 
Idmonea disticha, pars, de Blainville, 1834. Man. Act. p. 420. 
non,, ,, Michelin, 1845. Icon. Zoopli. p. 204, pi. lii. fig. 18. 
non,, ,, Ton Reuss, 1847. Foss. Polyp. MTien. : Xatnrw. Abh. toI. ii. 
p. 4o, pi. vi. figs. 29-31. 
,, von Hagenow, 1851. Bry. Maastr. Kr. p. 30, pi. ii. fig. 8. 
,, Seguenza, 1880. Formaz. terz. Begg. : Atti B. Acc. Line. 
ser. 3, Mem. vol. vi. p. 132. 
,, Hamm, 1881. Bry. mastr. Ob -Sen. p. 31. 
,, pars, Pergens A Meunier, 1887. Bry. gar. Faxe: Ann. Soc. 
roy. malac. Belg. vol. xxi. p. 213. 
,, Pergens, 1890. Bevision, p. 347. 
altei-nans, Bomer, 1840. Yerst. nordd. Kr. p. 21. 
inaciilata, pars, von Hagenow, 1851. Op. cit. p. 27, pi. ii. figs, ^e, f, g 
(non a-d). 
Retecava ,, pars, Hamm, 1881. Op. cit. p. 32. 
Tubigera distiqua, d’Orbigny, 1853. Bry. Cret. pi. 740, figs. 2-6. 
,, disticha, d’Orbigny, 1853. Ibid. p. 723. 
Ccriopora subcomprcisa, von Hagenow, 1839. Mon. Biig. : Xeu. Jahrb. 1839, 
p. 284. 
,, ,, von Hagenow, 1845. In Geinitz, Grundr. Yerst. p. 598, 
pi. xxiii. b, fig. 15. 
Fustulopwa ,, Bomer, 1840. Yerst. nordd. Kr. p. 21. 
Idmonea ,, Marsson, 1887. Bry. Biig. : Pal. Abb. vol. iv. p. 28, pi. ii. fig. 7. 
Stichopora regularis. d’Orbigny, 1851. Bry. Cret. pi. 613, figs. 11-15. 
Sdiatopora antiqua, pars, Defrance, 1827. Diet. Sci. nat. vol. xlviii. p. 496. 
Tubigera ,, d’Orbigny, 1853. Bry. Cret. p. 722, pi. 746, fig. 1. 
,, distans, d’Orbigiiy, 1853. Bry.' Cret. p. 724, pi. 746, figs. 7-11. 
Diagnosis, 
Zoaiium of laterally much compressed branches, which divide 
dichotomoiisly ; the sub-branches may anastomose into a reti- 
cular network. The branches in transverse section are bi- 
convex. The bare reverse surface is mdimentary. 
Apertui'es in series which extend almost round the branches, the 
reverse side being reduced to a naiTow line. The transverse 
series include Horn about six up to fifteen zooecia. Xear the 
reverse edge a few additional zooecia may occur. The trans- 
verse series are subalternate. 
Gonoevst a long ovoid chamber on the reverse suiTace. 
Dijiexsioxs. 
B.M., H. 3355. 
Breadth of a branch 
Thickness of a branch ... 
Diameter of zooecia 
Diameter of aperture ... 
Distance of transverse series 
•0 mm. 
•2 
•15 
•08--11 
•6 
