Keywords: The Quarterly journal of the Geological Society of London (12961660134).jpg 384 <br> PROCEEDINGS OF THE GEOLOGICAL SOCIETY <br> Fig 3 Scales of Gyrodiis coccoderma <br> June 23 <br> Mr Etheridge having kindly directed my attention to some spe- <br> cimens of Pycnodont teeth deposited in Jermyn Street hy Mr Man- <br> sel I found amongst them a fine example of the vomer of a <br> Cryrodus fig 4 which from its size may very possibly have belonged <br> to Gyrodus coccoderma This conjecture is strengthened by the fact <br> that it was found in the same stratum and in the same locality <br> viz in the Kimmeridge Clay of Kimmeridge The dentigerous area <br> of the bone measures two inches and eight-tenths in length The <br> breadth at the base is one inch and three-tenths and at the apex <br> seven-tenths of an inch It is furnished with five rows of teeth <br> The median row contains nine large circular tritores much abraded <br> on the grinding surface A tenth tooth is wanting at the base <br> Next in size come the marginal rows One of these contains <br> fourteen the other imperfect thirteen teeth They differ in form <br> from those of the median row in having the outer periphery trun- <br> cated and the outer edges raised Although somewhat used they <br> still retain the gyrations characteristic of the genus The inter- <br> mediate row contains the smallest teeth There are fourteen in <br> each row rather irregular in form but more or less circular The <br> surfaces are deeply furrowed as they have suffered little from use <br> This specimen differs from all the vomerine remains of Gyrodus <br> yet figured ; it approaches more nearly to a species named Pycnodus <br> Butertrei by M E Sauvage from the Portlandian rocks of Portel <br> which may possibly be a Gyrodus having the teeth much worn; 36103249 111288 51125 Page 384 Text v 25 http //www biodiversitylibrary org/page/36103249 1869 Geological Society of London NameFound Gyrodiis coccoderma NameFound Gyrodus NameConfirmed Gyrodus EOLID 21928535 NameBankID 4183624 NameFound Pycnodus NameConfirmed Pycnodus EOLID 4654792 NameBankID 4324329 Biodiversity Heritage Library The Quarterly journal of the Geological Society of London v 25 1869 Geology Periodicals Smithsonian Libraries bhl page 36103249 dc identifier http //biodiversitylibrary org/page/36103249 smithsonian libraries Information field Flickr posted date ISOdate 2014-03-06 Check categories 2015 August 26 CC-BY-2 0 BioDivLibrary https //flickr com/photos/61021753 N02/12961660134 2015-08-26 14 50 51 cc-by-2 0 PD-old-70-1923 The Quarterly journal of the Geological Society of London 1869 Photos uploaded from Flickr by FĂŚ using a script |