188 GLYPTICUS. 



The mouth opening is one half the diameter of the test, the peristome is unequally 

 decagonal, the notches are small, and the ambulacral are nearly twice as wide as the inter- 

 ambulacral lobes. 



Affinities and differences. — As this is the only species of the genus Glypticus found in 

 the English Oolites, it is impossible to mistake it : the thick test, with the hieroglyphic- 

 like markings on the plates of the inter-ambulacral areas, and of the genital disc, distinguish 

 it sufficiently from all others. 



Locality and Stratiyraphical position. — The rich cabinet of the late Mr. Channing Pearce 

 contains three specimens of this species, collected from the Coral Rag of Calne, Wilts ; and 

 in the Museums of York and Whitby I saw one specimen in each, which were collected 

 from Coralline Oolite of Malton. 



In France, M. Cotteau collected it at Chatel-Censoir and Druyes from the Inferior 

 Coral Rag, and the calcareo-siliceous layers subordinate to it. According to M. Desor it 

 is found in the Corallien (Terrain a chailles) of the Swiss and French Jura, of Burgundy, 

 Wiirttemberg, and Franconia. On the Continent it is a very abundant and characteristic 

 fossil of the Coral Rag, and is now recorded for the first time as a British urchin. 



History. — Leske appears to have considered this species identical with Cidaris 

 toreaumatica, Klein, he says, " Convenit hie Echinites omnino cum ipsa naturali Cidari 

 toreumatica, figura testae lineolis insculptis, ambulacris biporosis et ani structura, ut nulla 

 mihi relinquatur dutitatio, cum hujus esse speciei. Testa est calcareo spatosa, coloris 

 cinereo flavescentis ; nucleus calcareus griseus. In Lotharinyia inventus est."* 



Goldfuss figured and described it in his ' Petrefacta Germanias' by the name Echinus 

 hieroylyphicus. M. Agassiz, in his 'Prodrome,' placed it in the genus Arbacia, 

 but afterwards, in his ' Echinodermes Foss. de la Suisse,' proposed for this and other 

 congeneric forms, the genus Glypticus. In this work it is beautifully figured, and 

 described in detail as Glypticus hieroylyphicus. It has lately been figured by Bronn in his 

 ' Lethaea,' by M. Cotteau in his ' Etudes sur les Echinides Fossiles,' and by M. Desor 

 in his 'Synopsis des Echinides Fossiles.' and is now recorded for the first time as a 

 British fossil urchin. 



* ' Additamenta ad Kleinii dispositionem Ecliinodermatum,' p. 156, pi. 44, fig. 2. 



