■JiTi" 



THE AN>fALS 



AND 



MlGiZEXE OF NAT[JRAL HISTORY. 



[EIGHTH SERIES.] 

 No. 120. DECE:\IBER 1917. 



XLVIII. — British Fossil Crinoids. — XI. Balanocrinus of 

 the Loudon Clay. By F. A. Bather, D.Sc, F.R.S. 



(Published by perniissiou of tlie Trustees of the British Museum.) 



Before considering the somewhat obscure and relatively 

 rare stem-fragments of Pentacriuidae found in the London 

 (Jlay of England, it will be well to examine the corresponding- 

 fossils that are both abundant and well-preserved in the 

 Nummulitic rocks of Biarritz. The horizon from which 

 the crinoid stems are there obtained is now regarded as the 

 base of the Bartonian. Among the associated fossils are 

 Serpula spirulaea, Nuniniulites variolarius, and the nummu- 

 lite pair iV. contortus et striatus. 



Some specimens collected at the Port ties Barques, 

 Biarritz, by my friend Professor Jules Welsch, were recently 

 submitted to me by my esteemed correspondent Dom 

 Aurelien Valette, who desired my opinion on certain 

 observations that he had made on them. Since the facts to 

 which he directed my attention have for some thirty years 

 past been demonstrated in the exhibited series of fossil 

 crinoids at the British Museum (Natural History), as 

 mentioned in the ' Guide to the Fossil Invertebrate Animals ' 

 (1907 & 191], p. 63), it seems advisable to publish them 

 in more accessible and more extended form. Similar facts 



Ann. c& Mag. N. Hist. Ser. 8. Vol. xx. 2G 



