Notices respecting New Books. 217 



An Old Chapter of the Geological Record with a New Interpretation, 

 or Roch Metamorphism (especially the Methylosed hind), and its 

 resultant Imitations of Organisms : with an Introduction, giving an 

 Annotated History of the Controversy on the so-called Eozoon cana- 

 dense, and an Appendix. By Professors "W. King, Sc.D. Sfc, and 

 T. H. Kowney, Ph.D. 4-c. London : Van Voorst. 

 The present volume is the latest outcome of the Eozoon contro- 

 versy. It commences with an introduction of fifty-seven pages, 

 more than one fourth of the whole book, giving an epitome 

 of the literature (already formidable) which the discovery, rather 

 less than a quarter of a century since, of this supposed fossil has 

 already evoked. The different publications are arranged in chrono- 

 logical order, with abstracts of their principal contents. This is a 

 valuable part of the authors' work, and will form a useful compen- 

 dium of the Literature of the subject. It would, however, have 

 been still more valuable had it not been annotated, or if Messrs. King 

 and Kowney had been able to refrain from passing sarcasms, which 

 are often, to say the least, in bad taste, and occasionally, from their 

 obvious unfairness, arouse in the reader's mind a feeling of scepti- 

 cism as to whether the authors could possibly do justice to the 

 views of an adversary. They may no doubt plead in extenuation 

 that they are not the only sinners in this respect, perhaps that they 

 were not the first to import bad temper into a scientific discus- 

 sion ; at the same time, they would certainly have improved their 

 position, if they had preserved their equanimity in the historical 

 part of their work, and reserved their sneers and retorts for the 

 more controversial portion. 



The work itself discusses, after two or three preliminary chap- 

 ters on "ophites" in general, some wider questions concerning 

 mineralized and methylosed metamorphic rocks. By the former of 

 these terms is meant a rock which has had "the original substance 

 of its members crystallized into minerals of various kinds ; " by the 

 latter, one which has had " the same minerals altered or replaced by 

 chemical reactions." The distinction — which, however, is perfectly 

 well known to all petrologists, though the authors seem to treat it 

 as if it were a discovery — is undoubtedly an important one, though 

 in practice it is often by no means easily maintained ; and we may 

 consequently doubt whether it was worth while cumbering the lite- 

 rature of science with another word of foreign origin. The work 

 next passes on to discuss the origin of ophites. Here the authors 

 point out that serpentinization is effected in certain deposits with- 

 out the intervention of mineralization ; that many ophites were 

 originally sediments, others igneous rocks ; and discuss the origin 

 of hemithrene and other related calcitic rocks. Then comes a 

 chapter on the minerals characteristic of ophites and related rocks, 

 especially of peridote, followed by some on the origin of crystal- 

 line limestones, dolomites, &c, and on the age of ophites. 



A lengthy appendix follows, treating of various questions, some 

 of them rather remotely connected with the subject-matter of the 

 Phil. Mag. S. 5. Vol. 13. No. 80. March 1882. S 



