A MONOGRAPH 



OF THE 



TERTIARY ENTOMOSTRACA OF ENGLAND. 



In the introductory portion of my ' Monograph of the Entomostraca of the 

 Cretaceous Formation of England/ published by the Palaeontographical Society, 1849, 

 and also in my Notes on the Permian Entomostraca, at p. 58 of Professor King's 

 Monograph, of the same date, I offered some general remarks on fossil and recent 

 Entomostraca, and supplied numerous references to earlier observers who had written 

 on the subject. 1 



I need not repeat what is there stated. Since 1849 some highly important works 

 on the recent Entomostraca by Baird, Dana, Liljeborg, Zenker, Fischer, &c, have 

 appeared ; 2 and numerous valuable papers, illustrative of the fossil forms, have been 

 published by foreign Academies and Institutions. Amongst these palseontographical 

 works, the two Memoirs by M. J. Bosquet, of Maestrieht, on Tertiary and Cretaceous 

 Entomostraca, are pre-eminent ; and, at the same time, Dr. A. E. Reuss, of Prague, 

 has indefatigably produced several valuable and highly illustrated Memoirs, some of 

 considerable extent, on similar fossils. 



I do not propose to enter into a critical examination of the Tertiary species 

 described by these and other contemporary authors, for the figures published by 

 some of these writers are, either from their indefiniteness or the want of the illustra- 

 tion of details, of little use, even with the aid of the descriptions given, in satisfactorily 

 determining the differences or the specific identity of specimens ; 3 and I greatly regret 

 that I trusted too much to the illustrations of former authors, when I was comparing 



1 See also Bibliographical List, * Monog. Ent. Cret .,' p. 38. 2 See Bibliographical List, APPENDIX. 



3 Owing to the kindness of M. Bosquet, however, who has furnished me with a series of the Cretaceous 

 and Tertiary Entomostraca of Belgium and France, I have been enabled to compare many of the forms 

 described in this Monograph with their European congeners. 



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