252 APPENDIX TO THE SUPPLEMENTS TO 



10. Rhynchonella depressa, Sow. Dav., Cret. Mon., PL XI, figs. 28—32. 



We refer once more to this characteristic fossil in order to allude to the Rev. W. 

 Downes' paper on " Blackdown," published in the ' Transactions of the Devonshire 

 Association for the Advancement of Science, &c.,' 1880. In this paper the author states 

 that lithologically the Blackdown Hills may be said to consist in a descending series of — 



1st. An impersistent capping of chalk flints in a clayey matrix — 



2nd. Chert beds of varying thickness. 



3rd. Greensand, containing highly fossiliferous bands with concretions : the whole 

 very nearly horizontally stratified. 



It is remarkable how exceedingly rare is the occurrence of Brachiopoda in the Green- 

 sand bands of that celebrated locality. In the ' Cretaceous Supplement ' I allude to a 

 specimen of Rhynchonetta depressa, from Blackdown, in the Woodwardian Museum, 

 Cambridge ; since then Mr. Downes has kindly forwarded for my inspection two more 

 examples from the collection of Mr. Walrod, of Dulford House, near Collumpton, and he 

 assures me that, although Brachiopoda had been diligently sought for in the Blackdown 

 Greensand by himself and others, he had never seen more than the two specimens above 

 referred to, and that the Blackdown bands containing them are in all probability referable 

 to the upper part of the Lower Greensand. 



JURASSIC SPECIES. 



Subsequent to the publication of my ' Oolitic and Liassic Supplements,' the Inferior 

 Oolite in the counties of Dorset and Somerset has again been most diligently searched 

 for Brachiopoda by Mr. S. S. Buckman, F.G.S. He has described the larger number 

 of his new discoveries in vol. iv of the ' Proceedings of the Dorset Natural-History 

 and Antiquarian Club ' for 1882. In his Memoir, unfortunately unaccompanied by 

 figures, the author has been able to add materially to the number of species that I had 

 previously described and figured in the ' Proceedings ' of the same Club for 1877. 



The Inferior Oolite of those Counties has produced a very much larger number of 

 species and variations in form than any other British district hitherto investigated, and 

 for Inferior-Oolite species can be compared with that of Normandy. 



The Dorsetshire beds have been likewise thoroughly searched by Prof. Buckman, 

 Mr. D. Stephens, Mr. E. Cleminshaw, Mr. J. P. Walker, the Rev. G. F. Whidborne 

 and some others. The variety of forms that have turned up has been truly surprising. 



