128 THE LIASSIC PERIODS. CHAP. 



Myacites liassicus. Brod. L. Fenny-Compton. 



musculoides. Geol. Survey. R. Westbury. 

 ,, tenuistriatus. Ag. S. Frocester, Nailsworth. 



unionides. Geol. Surv. M. Tewkesbury, Dumbleton, Stinchcombe. 

 Myoconcha crassa. Sow. S. Nailsworth. 



Mytilus hippocampus. Geol. Surv. L. Berkley Heath. M. Nibley. 

 Nucula globosa. M. Stinchcombe. 



,, ovalis. Zieten. S. Nailsworth. 

 Opis carinata. Wright. S. Frocester. 

 Pholadomya ambigua. Sow. L. Bredon, Cheltenham, Fenny-Compton, Mickleton. 



M. Dumbleton, Stow. 

 ,, decorata. Goldf. L. Cheltenham. 



fidicula. Sow. S. Frocester, Nailsworth, Leckhampton. 



obliquata. Phil. L. Banbury. 



ovulum. Ag. S. Nailsworth. 



Pleurophorus elongatus. Moore. R. Westbury. 

 Pullastra arenicola. Stride. R. Westbury, Wilmcote. 

 Sanguinolaria striata. Geol. Surv. M. Stinchcombe. 

 Trigonia Ramsayi. Wright. S. Frocester, Leckhampton. 



striata. Sow. S. Frocester, Nailsworth. 

 Unicardium cardioides. Phil. L. Fenny-Compton, Chipping-Campden. M. 



Dumbleton, Bredon, Stow. 

 varicosum. Geol. Surv. M. Stow, Dumbleton. S. Nailsworth. 



Differing on the whole very much from the conchifera of the 

 palaeozoic formations, by the prevalence of Astarte, Cardinia, Corbis, 

 Hippopodium, and Pholadomya, which are unknown in them, we 

 find the continuity of life in the many-toothed genera like Area and 

 Cucullsea, which with Modiola and Sanguinolaria constitute a con- 

 siderable part of the early Dimyarian mollusks. Pullastra must be 

 regarded as of uncertain designation, and Myacites is an indefinite 

 group of species. Ceromya, Goniomya, Gresslya, Homomya, and 

 Pholadomya, which begin their career in the lias, have more oolitic 

 than liassic species. 



FOSSILS OF THE LIASSIC PERIOD. 



GASTEROPODA. 



Acmsea. sp. M. Uley. 



Actaeon. sp. L. Aston. 



Cerithium lineatum. L. Stonehouse, Cracombe, Aston. 



Chemnitzia. sp. U. Vale of Gloucester. 



,, Zinkeni. L. Fenny-Compton. 



Conus semicostatus (?). Goldf. M. Dumbleton. 

 Dentalium angulatum. Buckm. M. Alderton, Dumbleton. 



minimum. Strick. L. Cracombe. 

 Littorina. sp. L. Bredon, Aston. 

 Natica. sp. U. Vale of Gloucester. 



