223 



time yielded a large number of beautiful specimens ; the clay 

 in which, the Urchins were found formed the bottom of the 

 quarry; unfortunately this rich mine has become flooded, and 

 the fossiliferous beds are now under water. The following 

 species were collected many years ago from this zone near Calne. 



ECHINODERMATA. 



Cidaris florigemma, Phil. Holectypus oblongus, Wright, 



II Smitliii, Wright. Pygaster umbrella, Lamarck. 



Hemicidaris intermedia, Flem. Echinobrissus dimidiatus, Phil. 

 Pseudodiadema hemisplisericum, Ag. « scutatus, Lamarck. 



II versipora, Phil. Clypeus subulatus, Young and Bird. 



II radiatum, Wright. CoUyrites bicordata, Leske. 



II mamm.illanum., Poem. Pygtirus pentagonalis, Phil. 



Hemipedina corallina, Wright. " PMllipsii, Wright, 



II tuberculosa, Wright. « Blumenbachii, ^ocAtfcZ>MM/fce 



Glypticus hierogljrpbicus, Ooldf. n Hausmanni, « 



Stomechinus gyratus, Ag, Millericrinus eclmiatus, Schloth, 

 Acrosalenia decorata, Haime. 



The Coral rag, and beds with Cidaris florigemma, and 

 GlypiUus hieroglyphicus, constitute the two divisions of the 

 Coralhne Oolite in England, and represent the two zones into 

 which M. Maktin divides the Corallien of the Cote-d'Or. The 

 upper zone, included in M. de Neeville's section of gi'oupe 

 corallien, in descending order, includes calcaire a Nerinees, 

 calcaire a Astartes, and calcaire a Pteroceres, — the two first 

 form M. Martin's 



SfQUANIEN. 



This group is composed, according to our author, of — 



rCalcaires mamo-compactes a Astarte minima. 

 Calcaires m^ameux a Terebratula humeralis, 

 Seqtjanien. < Calcaires durs ou blancs crayeux a Nerincea Bruntrutana. 

 Calcaires blanchatres a Ostrea solitaria et Hemicidaria 

 \_ diademata. 



These terrains are considered by some to belong to the upper 

 division of the Corallian, and by others to constitute a distinct 

 formation intermediate between the Oxfordian and Kimmeridge 

 stages. The Sequanien is largely developed in several depart- 

 ments of France, especially in the Franche-Compte, comprising 

 R 



