Lankester — On the Suffolk Bone-bed and the Black Crag. 2.55 



In the November number of this journal, my friend, Dr. A. von 

 Koenen, of Marburg, does me the honour of criticizing the paper 

 which I published herein during 1865. As to matters of fact. Dr. 

 von Koenen and myself agree most closely, but he has taken excep- 

 tion to my use of the terms Pliocene and Miocene. I now regret 

 very much that I have ever used those terms at all ; and agree with 

 Mr. Godwin-Austen that they may tend to misunderstanding and 

 confusion. It is, however, I must submit, rather strange that a 

 geologist who adopts such an innovation as '' Oligocene" should be 

 severe on another as to the limitations of " Pliocene " and 

 " Miocene." I hereby desire to abandon these terms altogether in 

 speaking of the English and Belgian Crags, and by so doing I 

 believe that I leave myself in complete accord with Dr. von Koenen 

 as to the age of the Black Crag of Antwerp. It is a deposit which 

 may be classed very naturally with the other Crags, but differs 

 little from beds called Upper Miocene, agreeing with such 

 especially in its Cetacean and Shark fauna. Dr. von Koenen 

 also appears to have no high opinion of M. Nyst's concho- 

 logical investigations, of which I availed myself in estimating the 

 age of the Diestien and Scaldisien beds. In reply to this I must 

 refer to my paper (Geol. Mag., 1865, p. 149), in which I gave the 

 results of very careful analyses of the researches of Mr. Searles 

 Wood and M. Nyst, corrected by the aid of my much-regretted 

 friend Dr. S. P. Woodward. The per centage results which I 

 arrived at — so far as they have any value (and I think they have 

 considerable value) — are almost identical with those given by Mr. 

 Prestwich, through Mr. Gwyn Jeffreys, in a paper recently read at 

 the Geological Society. 



The paper by Mr. Prestwich just referred to, has the great value 

 which all the work of so eminent an observer carries. Hence I 

 feel some gratification in pointing out that he recognises the exist- 

 ence of the so-called Coprolite bed at the base of both Coralline 

 and Eed Crag, containing both terrestrial and marine mammalian 

 remains and Plagiostomous fish-teeth. This fact I first announced 

 in my paper already referred to. Mr. Prestwich also confirms me 

 in my observation of the different mineral condition of the " Copro- 

 lite bed " bones from that of those proper to the Crags. This fact 

 I dwelt on at some length in a paper in the Quart. Journ. Geol. 

 Society, 1865, p. 1423. Further, Mr. Prestwich agrees to my 

 deductions from these facts, and a study of the palaeontological 

 evidence, and he endorses my conclusion that the Cetacean and 

 Shark remains of the Coprolite-bed are derived from a previous 

 deposit of the age of the Systeme Diestien of Belgium.^ 



The existence in the Coprolite beds of a glauconitic sandy matrix 



1 In former papers I have spoken of the bed from which the Cetaceans originally 

 come as of Middle Crag age. This is an error; the Middle Crag of Antwerp is pro- 

 bably, as Mr. Godwin- Austen says, of Scaldisien age, with remaine Diestien forms 

 in it. There is no doubt that the Antwerp Cetaceans and Sharks belong truly to the 

 Diestien system, and hence it is to the derived Diesten fauna in the Middle Crag that 

 our Coprolite fossils are related. 



