1 .">•_> Scientific Intelligence. 



the laboratory work in courses in vertebrate anatomy in which 

 the eat is used as an object for dissection. The earlier editions 

 proved highly satisfactory for this purpose, and the present 

 revision, containing such changes as have been suggested by 

 practical experience and as are necessary to bring the work into 

 harmony with more recent views, will be equally useful. 



W. B. r. 



5. The Anatomy of Woody Plants; by Edward Charles 

 Jeffrey. Pp. x, 478, with frontispiece and 306 text figures. 

 Chicago, 1917 (The University of Chicago Press). — The study 

 of plant anatomy, in its historical and experimental aspects, has 

 been pursued with unusual success by Professor Jeffrey and his 

 students. In the present volume, which incorporates many of 

 the results of this work, the general subject is reviewed, and the 

 principles upon which its progress has been based are clearly 

 outlined. The most important of these principles are embodied 

 in the canons of recapitulation, conservative organs, and rever- 

 sion ; but in the application of these canons the greatest caution 

 is advised, in order to avoid unwarranted conclusions. The 

 importance of paleobotanical evidence is likewise emphasized, 

 and the attempt is everywhere made to support the conclusions 

 drawn from the study of living plants by observations on fossils. 



In the early chapters, after a general account of the cell and 

 of the tissue systems in the vascular plants, the individual tis- 

 sues and their disposition in the various plant organs are taken 

 up in detail. Later chapters interpret the affinities of the 

 main groups of the vascular plants, on the basis of anatomical 

 evidence, and discuss the influence of climatic changes on the 

 evolution of anatomical structures. The concluding chapter 

 deals with anatomical technique. 



The book is so full of important observations and deductions 

 that it is impossible to give an adequate idea of its contents in 

 a brief notice. Attention may be called, however, to certain 

 topics of more than usual interest, such as the derivation of the 

 various elements of wood (parenchyma, vessels, fibers, etc.) from 

 tracheids; the evolution of the wood ray from the primitive 

 linear condition, through the aggregate type, to the diffuse and 

 compound (parenchymatous) rays of the more advanced angio- 

 sperms; the retention of transfusion tissue in the sporangial 

 walls of the higher spermatophytes ; and the derivation of her- 

 baceous dicotyledons from woody ancestors, through the special- 

 ization of compound rays and the loss of secondary growth. In 

 the discussion of these and other topics of almost equal import- 

 ance the conclusions reached are usually based on evidence 

 drawn from several distinct sources, especially where the views 

 advanced are at variance with those commonly held. 



A. "W. E. 



