A MONOGRAPH 



INFERIOR OOLITE AMMONITES. 



It was with great hesitation that I offered to prepare a Monograph on the 

 Inferior Oolite Ammonites. I was, however, strenuously urged to do so by Dr. 

 Davidson, 1 to whom I am greatly indebted for every possible kindness and 

 encouragement, which I most gladly acknowledge. When I considered the vast 

 amount of study and labour that such a monograph would entail, and compared 

 the limited amount of time at my disposal owing to the cares of business, I was for 

 deferring my work or giving to others with more leisure the opportunity to under- 

 take the task. Dr. Davidson, however, pointed out to me the advantage that I 

 had of a very large amount of material collected during many years by my father 

 and myself, and also that I was acquainted with the different localities and 

 horizons from which the various species came, by having myself obtained and deve- 

 loped so large a number of them. This, however, only applies to a small area of 

 the Inferior Oolite in the South-west of England, and I must rely on the kindness 

 of correspondents to enable me to figure those species which occur in this 

 formation in other districts. It is, however, pretty well known that the Inferior 

 Oolite in the South-west of England contains a far larger proportion of Ammonites 

 than any other district except perhaps Dundry. With the Dundry beds I am not 

 actually acquainted, but the Ammonites that I have seen from them are certainly 

 in every way similar to ours in the South-west. 



As far as possible I intend to figure the best procurable examples, and also 

 enough specimens to show the different ages and variations of each species, 

 so that it may without doubt be easily recognised. It sometimes happens to be 

 a very hard matter to show in a plate the particular characters which dis- 



1 Since the above was written, I unfortunately have to say " the late Dr. Davidson." I cannot 

 take a better opportunity to express my sorrow, and to acknowledge the unfailing kindness which 

 I always received from him. 



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