Mr. T. R. Jones on Scandinavian Beyrichise. 83 



other specimens, and even shows the actually bivalved condition 

 of at least one example. This author refers all his specimens to 

 one species, under the name of Battus tuberculatus. 



In 1843 Burmeister (Die Organiz. d. Trilobiten, p. 72) refers 

 M. Kloden's figures, without any assigned reason and certainly 

 erroneously, to Odontopleura ovata. 



In 1846, M'Coy, describing the Silurian fossils of Ireland*, 

 pointed out the really unsymmetrical arrangement of the lobes 

 and furrows on these little bodies ; and, finding them to corre- 

 spond in pairs of dextral and sinistral valves, he rightly con- 

 jectured them to be the bivalved carapaces of Entomostraca. For 

 these animals he therefore established a new genus, " Beyrichiay^ 

 named from M. Bey rich, who also, in a work then lately pub- 

 lished f, had stated his belief that M. Kloden^s specimens were 

 not referable to any Trilobite, but to some small bivalved Crus- 

 tacean. 



In 1851 1 Prof. M^Coy further illustrated the genus, referring 

 it to the family " Limnadiadse,^^ of the Phyllopod order of Ento- 

 mostraca ; and remarking that " several species of this genus 

 have been figured and described by Kloden, as varieties of his 

 Battus tuherculatm?^ 



Mr. Salter also has illustrated and described some British 

 species of this genus, in the Memoirs of the Geological Survey 

 of Great Britain, vol. ii. part 1, and in Appendix A. of ' Descript. 

 Brit. Pal. Foss.' above referred to. There are a few other pub- 

 lished notices of BeyrichicB ; but we now have to confine our- 

 selves to an examination of the species from the Scandinavian 

 limestone, postponing for the present the critical notice of other 

 published species. 



As M. Kloden's figures were nearly all that we had in this 

 country for our guidance in the comparison of the Beyrichice, it 

 was desirable that we should be able to test by the examination of 

 good Scandinavian specimens the accuracy of these drawings and 

 of the specific determinations that have been made by their help. 

 Not long since Sir C. Lyell, when visiting Berlin, had the kind- 

 ness to mention to Prof. Beyrich ray desire to have an oppor- 

 tunity of examining some well-preserved specimens of M. Klo- 

 den^s typical species ; and a liberal supply of limestone fragments 

 from the gravels of Prussia and Silesia, rich in Beyrichice, was 

 most courteously granted by Prof. Beyrich and brought to En- 

 gland by Sir C. Lyell. 



I now proceed to the results of the examination of these inter- 



* Synopsis of the Silurian Fossils of Ireland (4to, Dubhn), p. 57- 

 t Ueber Einige bohmische Trilobiten, p. 47. 



X Description of Brit. Pal. Foss. in Sedgwick's Synopsis of the Classi- 

 fication of Brit. Pal. Rocks. 4to, Cambridge. Part II. Fasc. 1. p. 135. 



6* 



