274 NATURAL SCIENCE [October 



subject of fossil plants. Laymen might find in such a list of blunders 

 a mere comedy of errors, but the palaeobotanist must see in them 

 serious warnings against dogmatic conclusions or expressions of 

 opinion on imperfect data and insufficient evidence " ; and it is in 

 this spirit, not one of severe criticism, that we must study many of 

 the earlier writers. 



Nomenclature is dealt with in chapter vi., and though a text- 

 book is not the place to treat fully this " difficult and thorny ques-' 

 tion," the general principles are laid down for the protection of the 

 name of the original describer as the author of the species, even 

 though circumstances demand its removal to another genus than that 

 in which it was originally placed. 



Part II., beginning at chapter vii., deals with the systematic portion 

 of the subject. The divisions of the plant kingdom are taken in 

 their natural sequence, beginning with the lowest and passing 

 gradually to the highest group. The Thallophyta are therefore 

 first considered, the various groups or genera being preceded by 

 a short account of their recent representatives. Here are included 

 the Girvanella of Nicholson and Etheridge. The supposed fossil 

 bacilli are described in some detail, and though some minute 

 bodies are possibly correctly included here, a great deal of un- 

 certainty hangs over many of these so-called Bacteria. 



The Algae form a difficult class. Undoubtedly most of the fossils 

 originally described as Algae are inorganic markings and animal 

 tracks, though a few true Algae have been found in the fossil state — 

 even in palaeozoic rocks. Examples of tracks simulating Algoidal 

 structures are given which will illustrate the difficulties in dis- 

 tinguishing between true fossils and inorganic markings. We believe- 

 Mr Seward is correct in the doubts he holds as to the vegetable 

 nature of Chondrites verisimilis, Salter. 



It is impossible to refer in detail to the many interesting points- 

 touched on by the author in his admirable treatment of this very 

 difficult class of fossils, but Ncmatophycus — the Prototaxitcs of 

 Dawson — deserves a passing notice. This plant is very fully gone 

 into by Mr Seward, who arrives at the conclusion that " on the 

 whole it is probably the better course to speak of Nematophycus as a 

 possible ally of the brown Algae rather than as an extinct type of 

 the Siphoneae," and this is going quite as far as our knowledge of the 

 fossils warrants. 



In chapter viii. the Bryophyta are considered. We are here 

 treading on very difficult ground, and especially in regard to those 

 species discovered in the older rocks, none of which seem to be alto- 

 gether free from doubt. 



When we reach the Pteridophyta, chapter i.v, one possesses more 

 certain data from which to form an opinion of the affinities of the 

 various fossils described, though even here there is room for much 

 difference of opinion. 



The Equisetaceae are first described, — a sketch of Equisctum 

 prefacing the study of its fossil allies, and here are met with some of 

 the most interesting fossils one requires to consider. 



The genus Equisctum has been recorded by several writers from 

 Palaeozoic rocks, but Mr Seward places all these in Equisetites, and as 



