PLATE XIV. 



(Carboniferous Species.) 



1 — 5. Cyrtina septosa, sp. Phillips. From Park Hill, Longnor, Derbyshire. In the 



Museum of Practical Geology. 



6. — — Interior of the ventral valve. 



7. — — Specimen from which a portion of the shell has been removed 



so as to expose the combined mesial septa (s) and dental 

 plates (r) seen in profile. 

 B. — — Fragments of the ventral valve of a specimen from Ribble Head. 



In the collection of Professor PhiUips. To show the position 

 of the conjoined septa (s), and dental plates (ii). 

 9. — — • Another fragment of the same valve in the cabinet of Mr. Reed, 



of York, (s) conjoined septa. 

 10. — — An internal cast of the ventral valve in red dolomitic limestone. 



From Ashby de la Zouch. Museum of Practical Geology. 



