BOOKS AND CURRENT LITERATURE 



Fossil Plants. — The fourth and concluding volume of the Cam- 

 bridge text on fossil plants, is devoted to a consideration of the Gink- 

 goales, Coniferales and Gnetales. 1 The final proofs were passed in the 

 Spring of 1918 but the printing was held up because of war conditions 

 so that a number of recent contributions could not be considered. The 

 method of treatment in the present volume is consistent with that of 

 the preceding volumes and the same lack of balanced treatment is 

 shown in the present work. To cite but a single instance of this, six 

 lines are devoted to the remains of Ginkgo from North America although 

 Ginkgo is exceedingly well represented in the Mesozoic and early Ecoene 

 on this continent. 



As regards the subject matter, a chapter is devoted to the Ginkgo- 

 ales, recent and fossil. The second chapter considers Ginkgoidium, 

 Czekanowskia, Feildenia, Phoenicopsis and Desmophyllum, — genera that 

 are believed to belong to the Ginkgoales. The third chapter includes 

 supposed Ginkgoalean genera of still more doubtful allegiance. The 

 nine following chapters are devoted to the Coniferales. There is a 

 rather full and excellent account of recent Conifers. These are grouped 

 in the following nine families: Araucarineae, Cupressineae, Callitrineae, 

 Sequoiineae, Sciadopitineae, Abietineae, Podocarpineae, Phylloclad- 

 ineae and Taxineae. They are considered as probably monophyletic, 

 the Araucarineae being regarded as the most ancient and the Abie- 

 tineae as the most modern. There are some illuminating discussions 

 of vascular anatomy, and the view is expressed that the cone scales in 

 the Araucarineae are morphologically simple ovuliferous leaves, the 

 double cone scales of the Abietineae being derivatives of a simple form 

 of sporophyll. Mesembrioxylon is proposed for the fossil woods for- 

 merly referred to Podocarpoxylon and Phyllocladoxylon. The final chap- 

 ter is devoted to the Gnetales and is without noteworthy features. 



Opinion will differ as to the necessity or desirability for some of 

 the new generic terms that are proposed, e.g., Ginkgoites for Ginkgo 

 leaves, on the ground that even in the Tertiary forms the confirmatory 



1 Seward, A. C. Fossil Plants. Vol. IV. Cambridge University Press (New 

 York, G. P. Putnam's Sons) 1919. 



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