ON THE OSTKACODJL OF THE TUEBECK FOEMATION. 311 



29. On the Ostracoda of the Puebeck Foemation ; luith Notes on 



the Wealden Species. By Prof. T. Eupeet J'o:n^es, F.R.S. 



P.G.S., &c. (Eead May 13, 1885.) 



[Plates VIII. & IX.-^] 



Contexts. Page 



§1. Introduction 311 



§ n. Ostracoda of the Purbeck Formation. — Sources of Information ... 312 

 Sir C. Lyell's woodcuts, and the Diagrams at the Museum of 



Practical Geology 312 



E. Forbes's two Letters 314 



Vertical Sections (Geological Survey) at Durlston Bay, Wor- 



barrow Bay, Mewps Bay, and Eidgway Hill 315 



BE. W. Bristow's, J. H. Austen's, and O. Pisher's Lists of Pur- 

 beck strata 315 



Fitton and Sowerby in Fitton's memoir (Trans. Geol. Soc. ser. 2, 

 vol. iv. 1836), and Dr. Fitton's specimens in the Geological 



Society's Museum 315 



Specimens in the Museum of the Geological Society, Museum of 

 Practical Geology, and British Museum, and communicated 



specimens 317 



§ III. Ostracoda of Wealden and reputed '•' Wealden " strata 317 



E-omer's and Dunker's species 318 



Shotover and jS'etherfield specimens 320 



Synonyms of Oypridea Austeni 321 



§ IV. Catalogue of definite localities and horizons in the Purbeck 



Formation, with their Species 321 



L Upper Purbecks 321 



IL Middle Purbecks 323 



III. Lower Purbecks 325 



IV. Species from Moimtfield. Poundsford, and Netherfield 330 



V. Species from Swindon, collected by Mr, C. Moore 330 



§V. Conclusion 331 



§VI. Tabular Conspectus of the Purbeck Ostracoda 332 



§ VII. Appendix : 



1. Ostracoda of the Wealden Formation 333 



2. Sj-noptical List of the Purbeck and Wealden species in England 335 

 § Vni. Description of the Species 336 



Explanation of the Plates 351 



§1. I^^teoduction-. 



In the ' Geological Magazine,' dec. 2, vol. v. (March and June 1878), 

 pp. 103 & 277, I offered some observations on the Ostracoda of the 

 Purbeck and "Wealden Formations, and endeavoured to determine 

 the species already described and figured by Sowerby, Fitton, 

 F. A. Eomer, and W. Dunker, and by E. Forbes, Lyell, anc P. de 

 Loriol. One of these species was further noticed (as Qytherel 

 purhecketisis) in the ' Proceedings of the Geologists' Association,' 

 vol. viii. 1883, p. 58, together with an additional species which I 

 had defined as Cythere boloniensisf [bononiensis] in the Bull. Soc. Ge'ol. 

 France, ser. 3, vol. viii. 1882, p. 616. 



^ These Plates have been drawn by aid of a grant from the Royal Society, 

 for the illustration of Fossil Entomostraca. 



t jS'ow corrected to bononiensis, in accordance with the Latin name of Bou- 

 logne, " Bononia.'" 



2z 



