178 BRITISH PALAEOZOIC SPONGES. 



The figure given is a very imperfect representation of the original, which is 

 said to be from Coniston. 



54. Botheoconis plana, King. 



1850. Mon. Permian Toss., Pal. Soc, vol. iv, p. 13, pi. ii, fig. 6. 



The original specimens, now in the Museum of Queen's College, Galway, con- 

 sist of shallow, circular depressions on the weathered surfaces of shelly limestone. 

 In some instances the pits are close together, whilst in others there are consider- 

 able interspaces between them. Their origin is problematical ; they may be due 

 to mere weather-erosion since the limestone was exposed. They are certainly not 

 Sponges. 



The types are from Magnesian Limestone (Permian), Tunstall Hill, Durham. 



55. Cnemidium tenue, Lonsdale. 



1839. Murchison's Silurian System, p. 694, pi. xvi bis, figs. 11, 11 a, 11 b. 



The original specimen, shown on the weathered surface of a slab of Wenlock 

 Limestone, now in the Museum of the Geological Society of London, appears to be 

 either a small coral or a polyzoon. It is from Dudley. 



56. Coscinopora placenta ? Lonsdale (non Goldfuss). 



1840. Transactions Geological Soc, ser. 2, vol. v, pi. lviii, figs. 5 a — 5 d. 



The original belongs to the Stromatoporoid group, and is the form known 

 subsequently under the name of Caunopora placenta. It occurs in the Devonian 

 Limestone of Plymouth and Torquay. 



57. Entobia antiqua, Portloch. 



1843. Eeport on the G-eology of Londonderry, &c, p. 360, pi. xxi, figs. 5 a, 5 5. 



Judging from examples of this species now in the Museum of the Geological 

 Survey, Jermyn Street, which correspond closely with Portlock's descriptions and 



