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the two fossils as Feistmantel and Velenovsky have previously 

 suggested." The anatomical evidence ou which this statement 

 depends is fully given on p. 157. 



So far as the imperfect material enables us to judge, it seems 

 probable that the various families of ferns were represented in the 

 Wealden formation much as at the present day. There seems, 

 however, to be as yet a marked absence of evidence for the identifi- 

 cation of the Marattiacece, which played so predominant a part in 

 earlier geological epochs. It may be hoped that further discoveries 

 will throw some light on the position of this family in the Wealden 

 Flora. 



Mr. Seward has done his work in a most complete and satis- 

 factory manner, and in the difficult question of species, especially, 

 he seems to have followed a via media with great success. The 

 plates, all but one of which were drawn by the Misses Woodward, 

 are admirably executed, and form a most valuable feature of the 



Experimental Plant Physiology. By Dr. Walter Oels. Translated 

 and edited by D. T. Macdougal. 8vo, pp. x, 86, with 77 

 illustrations. Morris & Wilson, Minneapolis, Minnesota. 

 1894. 



In the English edition of Dr. Oels' manual Mr. Macdougal has 

 produced a convenient laboratory guide to a series of experiments 

 illustrative of the more important factors in the life of a plant. 

 Primarily designed for use in the summer schools, university ex- 

 tension, and other schools in connection with the University of 

 Minnesota, it will doubtless be welcomed by the teacher or lecturer 

 engaged in connection with similar undertakings elsewhere in 

 America and in Great Britain. The apparatus required to carry 

 out the experiments is comparatively simple, and easily acquired ; 

 such physical and chemical apparatus as should be found in any 

 good school or college laboratory being sufficient for nearly all. 

 The use of the term "Photo-synthesis" for the "assimilation of 

 carbon dioxide from the air by the green parts of a plant in sunlight 

 is an innovation. While admitting the necessity for a term to 

 describe this process, we do not think Prof. Couway MacMillan's 

 suggestion the best possible. 



The book contains directions for 122 experiments arranged 

 under ten sections, viz., absorption of nutriment, transpiration, 

 photo-synthesis, respiration and metabolism, geotropism, helio- 

 iropism, warmth, growth, movement, and relations of plants to 

 animals. The many excellent illustrations will be found most 

 helpful to their performance. The text is clear and well arranged, 

 though misprints are not uncommon, while German-English and 

 sentences which won't analyse occasionally occur. 



book. They are supplemented by 



woodcuts in the t 

 D. H. 



A. B. R. 



