PREFACE. 



In presenting the First Part of my Monograph on ' British Fossil Echinodermata ' to 

 the members of the Palseontographical Society, I deem it necessary to make a few remarks 

 in order to explain — 1st, how I came to occupy the position of an author in the magnifi- 

 cent volumes published by your Society ; and 2dly, to state the manner in which I have 

 endeavoured to discharge the duties of the task I have undertaken. 



After the publication of my ' Memoirs on the Echinodermata of the Oolites,'* in the 

 ' Annals of Natural History,' my much lamented friend, the late Professor Edward Forbes, 

 as a member of your Council, asked me to contribute a Monograph on the same subject 

 to the Palseontographical Society. Knowing that he had in preparation a supplementary 

 chapter on the Echinoderms of the Great Oolite, for Messrs. Morris and Lycett ; s 

 Monograph on the Mollusca of that Formation, I thanked him for the good opinion he 

 had formed of my ability for such a work, but declined, lest, by complying with his request, 

 I might possibly have interfered with any intentions of his own on the subject, knowing 

 how ardently he loved all that related to this class of the Animal Kingdom. As Professor 

 Forbes, however, on another occasion, renewed, in the most pressing manner, his solici- 

 tation, I then proposed to join him in a Monograph on the British Fossil Echinodermata 

 of the Secondary Formations, which he at once agreed to, and the proposal for this joint 

 work was submitted to the approval of your Council, and received its sanction. 



The numerous and constantly increasing duties of my esteemed colleague at the School 

 of Mines prevented him from taking any share in the collection of materials for the prepa- 

 ration of the Monograph on the Oolitic Echinodermata, and, with his usual candour, he 

 told me that, as he was unable, from want of time, to contribute to this division of our 

 proposed joint work, his name must be withdrawn from its title page ; and, if agreeable to 

 me, that I should undertake the Monograph on the Oolitic species, whilst he would devote 

 himself to the description of the Cretaceous forms. After this arrangement, I directed my 

 attention with redoubled energy to the subject of my special studies. 



On his appointment to the chair of Natural History in the University of Edinburgh, 

 Professor Forbes took with him the materials for the first part of his promised Monograph 



* 'Annals and Magazine of Natural History,' new series, vol. viii, 1851. 



