8 BRITISH CRETACEOUS BRACHIOPODA. 



Plate I, fig. 29. A specimen from the Upper Green Sand, near Warminster, in the 



Collection of the British Museum. 

 „ fig. 29 a . A specimen, showing the interior and muscular impressions 



enlarged, likewise from the same locality, in the Collection of 



the British Museum. 

 „ fig. 30. Another specimen, from the Collection of Mr. Cunnington. 



Genus — Crania, Retzius. 1781. 



Shell inequivalved, circular, or subquadrate, more or less irregular, entirely or 

 partially attached by the substance of its smaller valve to rocks, or other submarine bodies. 

 Upper valve conical, with lateral or subcentral vertex, without hinge or ligament : four 

 circular muscular impressions in each valve. Surface smooth, or longitudinally striated ; 

 arms fleshy, with spiral extremities; no calcareous supports. Structure strongly 

 punctuated. 



Some authors state to have found four or five species of British Cretaceous Cranias, but 

 all our researches have only brought to light two, viz., C. Parisiensis, and C. Egnabergensis. 

 Of those mentioned, some are only synonyms ; others, such as C. spinulosa, Nilsson, and 

 C. costata, Sow., seem founded on erroneous determinations. 



3. Crania Parisiensis, Defrance. Plate I, figs. 1 — 7. 



Crania Parisiensis, Defrance. Die. des Sc. Nat. vol. ii, p. 313, No. 3, 1819. 



— — Lamarck. An. Sans. Vert., vol. vi, p. 239, 1819. 



— — Brongniart. Desc. Geol. des Env. de Paris, pi. iii, fig. 2, 1822. 



— — Sow. Min. Con., vol. v, p. 3, tab. 408, 1825. 



— — Hceninghaus. Mon. des Cranies, p. 9, fig. 8, 1828. 



— — Besh. 1830. Ency. Meth., ii, p. 18, No. 8. 



— — Besh. Nouv. Ed. de Lam., vol. vii, p. 300, No. 3, 1836. 



— — Bujardin. 1837. Mem. de la Soc. Geol. de France, vol. ii, p. 222. 



— — Goldfuss. Petref. Germ., p. 293, pi. 162, fig. 8, 1840. 



— — B'Orb. Pal. Franc. Ter. Cre'tacees, vol. iv, p. 139, pi. 524, 



figs. 8—13, 1837. 



— — Rcetner. Die vers Norddeutschen Kreidgeberges, 1840, p. 36, No. 3. 



— — V. Hagenow. Jahrb., f. min., 1842. 



— — Morris. Catalogue, 1843. 



— — Reuss. Die Verstein. der Bdkemischen Kreideformation, 1846, 



p. 53, No. 2. 



— — Tennant. A Stratigraphical List of British Fossils, p. 47, 1847. 



— — Bronn. Index Palaeontologie, p. 342, 1848. 



— — B'Orb. Prodrome, vol. i, p. 259, 1850. 



— — Bixon. The Geology of the Tertiary and Cretaceous Formations 



of Sussex, p. 354, pi. xxvii, fig. 9, 1850. 



