242 



AMERICAN FORESTRY 



contains a key to some of the European 

 woods. The author does not give a 

 •great deal of original matter in this 

 book ; the analytical key appears to be 

 chiefly from Dr. Robert Hartig's "Tim- 

 bers and How to Know Them." 



Students of wood structure in Amer- 

 ica are less numerous. Chief among 

 those who have done orginal research 

 is Dr. D. P. Penhallowj whose labors 

 on the North American Gymnosperms 

 extend over a period of twenty years. 

 He is easily the greatest living authority 

 on the anatomical characters of the 

 North American Gymnosperms. Ro- 

 meyn B. Hough's sections of woods de- 

 serve praise, for they offer the named 

 wood itself for comparison which lends 

 much assistance to dealers in American 

 woods. Among others who have done 

 work along this line are Roth of Michi- 

 gan University, Jeffery of Harvard 

 University, Sudworth of the United 

 States Forest Service, Toumey of Yale 

 University, and Snow of New York 

 University. 



It is to the Germans that we must 

 look for substantial progress in this 

 work, and chief among them is Radlko- 

 fer and the botanists of his school. Dr. 

 Hans Solereder worked out a classifi- 

 cation based on purely morphological 

 characters. Unfortunately, however, 

 he confined himself to the examination 

 of small twigs, and consequently includ- 

 ed characters that belong only to pri- 

 mary wood, which yields few characters 

 present in market samples that consist 

 wholly of secondary wood. Nordlin- 

 ger has briefly described i,ioo species 

 from small transverse sections. A num- 

 ber of these sections, however, as is true 

 also of Solereder's, are taken from small 

 twigs which do not show structures 

 characteristics of secondary wood. 

 Nordlinger did not make a key for 

 tracing down the woods to the group 

 to which they belong. Although a num- 

 ber of German botanists have confined 

 their attention to particular groups of 

 woods, they have accomplished a great 

 deal of good. Among them are Abro- 

 meit on the Cupuliferae ; Beyer on the 

 Anonaceae ; Burgerstein on the Pom- 

 aceze; Dippel and Mayr on the 



Coniferae ; Goppert on the Magnoli- 

 acese ; Hitzemann on the Dipterocar- 

 pacege and Chloenacege ; Jaensch and 

 Saupe on the Leguminacese : Knob- 

 lauch on the Laurinaceae ; Moll, Jans- 

 sonius, Reinsch, Schroder, Schwartz. 

 Springer, etc. Altogether a great deal 

 has been done by the different investiga- 

 tors toward making a key based on the 

 anatomical characters found in wood. 

 If the knowledge now accumulated in 

 English and German publications could 

 be simply compiled a very valuable 

 work would be done. 



THE IMPORTANCE OF MICROSCOPICAL 

 RESEARCH 



An investigation of this kind has al- 

 ways been considered one of great im- 

 portance, and it does not require any 

 extended defense. What is needed is 

 simply the collection and determination 

 of special, well-chosen structures, so 

 recorded that they may be readily re- 

 ferred to when needed. 



If only a few objects are to be classi- 

 fied it may not be necessary to compile 

 very many distinguishing characters, 

 but when the objects run up into the 

 thousands it becomes necessary that the 

 characters employed in a key be multi- 

 plied accordingly. The required num- 

 ber of characters can not be determined 

 by the unaided eye or even with a hand 

 lens ; on the contrary it may require the 

 closest observation with the highest 

 power of the compound microscope in 

 order to detect a sufificient number of 

 constant characters. Objections have 

 been, and may well be, raised against 

 such microscopical research on the 

 ground that the results will be too tech- 

 nical to be useful to the mass of wood 

 users most in need of a key. English 

 timber merchants have tried for many 

 years to prepare a key based on the 

 more obvious gross characters for the 

 reason that they are not equipped to 

 make a microscopical examination of 

 woods. The time has arrived, however, 

 when the number of foreign woods in 

 general use is becoming so great that a 

 knowledge of the gross characters alone 

 will no longer answer as means of iden- 



