Reviews — Murchison's " Siluria,^* 83 



found in the Lower, Middle, and Upper Silurian formations; but 

 there are also notices and woodcuts of Graptolites, Starfishes, Eury- 

 pterids, Corals, and many other fossils in the earlier chapters, 

 where they come in as characteristic of the strata there treated of — 

 there are others scattered through the after-portion of the work — and 

 the Appendix contains not only supplemental palseontological notes, 

 but a good synopsis of the Graptolites (by Mr. Carruthers), and 

 an elaborate Table of British Silurian fossils, as now known, 

 classified zoologically, and referred to their respective formations. 

 This Table was greatly improved and augmented in the Second 

 Edition by Mr. Salter ; and now, in the Third, it has received nearly 

 300 additional species. At the same time, we may notice that 

 several published species are omitted, because a careful examination 

 has shown their identity with others previously described ; and the 

 student will observe also " that many of the long-known names of 

 Silurian fossils have been exchanged for more correct names, accord- 

 ing to the recent determinations of their real alliances, often obscure 

 before, and only established on the discovery of more perfect 

 specimens, and by an extended knowledge of extinct forms of life." 

 This revised Table has been prepared by Mr. Etheridge, assisted by 

 Professors Morris and Jones, who have had the help of Davidson, 

 H. Woodward, Carruthers, and Duncan, in their special subjects of 

 Brachiopods, Crustacea, Graptolites, and Corals ; and they have had 

 also the benefit of Mr. Salter's latest researches in Silurian Trilobites, 

 Mollusca, etc., as well as the manifold labours of Barrande, James 

 Hall, Billings, M'Coy, Baily, Edgell, Holl, and others, both at home 

 and abroad. Not only in the Table, but in the body of the work, 

 and in the Explanations of the Plates, the improved nomenclature 

 has been adopted (a few exceptions are indicated in the list of 

 Errata), many old names having been " exchanged for others more 

 correct as to generic and specific affinities, or entitled to use by 

 priority." 



The life -history of the Silurian age has thus been greatly eluci- 

 dated, not only by the better zoological and geological classification 

 of the known fossils, but by the many new forms (especially 

 of Paradoxides, Conocoryphe, and other Trilobites) obtained from the 

 Lingulella-flags ("Primordial Zone"), and from the Tremadoc 

 Slates, by Messrs. Salter, Hicks, Homfray. and Ash (p. 202, etc.), 

 indicating the succession of a deep sea, alive with Invertebrates, to 

 the almost barren shoal waters that deposited the *' Cambrian " 

 muds and sands, with no trace of former life in them in Canada and 

 Scotland, with a minute LinguhUa at David's, and with little enough 

 where the Longraynd has raised up the old schistose, rippled, sun- 

 cracked, and burrowed mud-banks, as part of the '• Silurian " land. 



For both the earlier and the later formations of the Silurian 

 system, their life-history is also made clearer by the increased number 

 of Trilobites worked out by Salter, Eurypterids by H. Woodward, 

 small En(omostraca by Jones and Holl, Brachiopods by Davidson, 

 Graptolites by Carruthers and Nicholson, etc. There will be dif- 

 ferences of opinion as to the exact allocation of some of the new 



