480 BOTANICAL GAZETTE [December 



the tree species involved, the processes of manufacture, the marketing, the 

 utilization, and values are discussed. Whenever any attempts have been made 

 toward standard specifications and grading of the products, these are given 

 in considerable detail. Statistics of production in the United States or of 

 importation from other lands are arranged in convenient tables, and still more 

 important for the scientist is the bibliography which is appended to each chap- 

 ter. Costs of raw material, labor, overhead, and marketing are considered, 

 as weU as selling prices and total value of production; while a detailed index 

 makes this mass of information available for ready reference. — -Geo. D. Fuller. 



Economic woods 



Record's^ presentation of the subject of wood structure has already 

 made his book, in its first edition, indispensable in all laboratories where the 

 identification of wood is attempted, on the basis of its structure as revealed 

 through the microscope. The volume has also proved equally useful in classes 

 where the general principles of wood structure are being studied, hence an 

 enlarged second edition will be welcomed by a considerable constituency. 



Among the desirable features of the work are good clear illustrations 

 (whose number might be increased to advantage), logical organization, con- 

 cise statement, convenient tables for reference, and a well arranged, excellent 

 bibliography, which in the present edition is brought down to 1918. The 

 identification key has been revised and improved and appears adequate to the 

 demands likely to be made upon it. 



One of the features of the new edition is an appendix devoted to a general 

 description of the woods of the United States and their classification on a 

 structural basis. Tables giving the occurrence of such structures as pits, 

 spiral markings, and tyloses in various genera and species afford convenient 

 means of classification and of easy reference. — Geo. D. Fuller. 



NOTES FOR STUDENTS 



Influence of a crop on succeeding one. — Hartwell and his associates* 

 have done some very important work on the influence of crop plants on those 

 which follow. Some crops are very injurious to those which follow them, while 

 other successions reveal no injurious action. As is shown by an illustration on 

 the front cover of Bulletin 175, buckwheat is greatly injured when it follows 

 miUet, but shows good development when it follows turnips. The method, 



s Record, S. J., Identification of the economic woods of the United States. 

 8vo. pp. 157. pis. 6. figs. 15. New York: Wiley & Sons. 1919. $i.7S- 



* Hartwell, B. L., and Damon, S. C, The influence of crop plants on those which 

 follow. Bull. 175. Agric. Exp. Sta. R.I. State College. 1918. 



Hartwell, B. L., Pember, F. R., and Merkle, G. E., The influence of crop 

 plants on those which follow. Bull. 176. Agric. Exp. Sta. R.I. State College. 1919. 



