248 



STRATIGRAPHICAL GEOLOGY 



Phillipsia, Griffithides, Proetus, Cyphaspis, and Brachymetopus. None 

 are common, all are small, and all died out, in Europe at any rate, 

 before the close of the period. Small Ostracoda are often abundant 

 belonging to the genera Bairdia, Cypridina, Cypridinella, and 

 others. Dithyrocaris and other Phyllocarids also occur. Schizopoda 

 are also represented and are common in some parts of Scotland. 



Fig. 83. GROUP OF CARBONIFEROUS FOSSILS (AVONIAN). 



a. Platycrinus leevis. d. Phillipsia pustulosa. 



6. Palsechinus gigas. e. Ccelonautilus cariniferus. 



c. Granatocrinus ellipticus. /. Gastrioceras Listeri. 



g. Orthoceras Gesneri. 



Brachiopoda. The only common and distinctive Carboni- 

 ferous genus is Seminula, but most of the Devonian genera survive, 

 such as Orbicidoidea, Productus, Spirifer, Spiriferina, Rhynchonella 

 (Pugnax and Hypothyris), Camarophoria, Dielasma, Athyris, Chonetes, 

 and Orthis. 



Lamellibranchia. The following are some of the com- 

 moner genera, those with an asterisk making their first appearance : 

 Pterinopecten, Aviculopecten, Crenipecten, Posidoniella* Parallelodon , 



