ECONOMIC WOODS OP THE UNITED STATES 71 



Pits (pp. 31-35) 



Bailey, Irving W.: The Preservative Treatment of Wood. II. 

 The Structure of the Pit Membranes in the Tracheids of Conifers 

 and their Relation to the Penetration of Gases, Liquids, and 

 Finely Divided Solids into Green and Seasoned Wood. For. 

 Quarterly, 11: 1: 12-20, Mch. 1913. 



Bailey, Irving W. : The Structure of the Bordered Pits of Conifers 

 and Its Bearing upon the Tension Hypothesis of the Ascent of 

 Sap in Plants. Bot. Gaz., 62: 2: 133-142, Aug. 1916. 



Brown, Forest B. H.: Variation in the Size of Ray Pits of Coni- 

 fers. Ohio Naturalist, 15: 542-550, June 1915. 



Tyloses (pp. 35-36) 



Gerry, Eloise: Tyloses: Their Occurrence and Practical Signif- 

 icance in Some American Woods. Journ. Agr. Research, 

 1:6:445-470,1914. 



Pith Flecks (pp. 36-37) 



Brown, H. P.: Pith-ray Flecks in Wood. Cir. 25, U. S. Forest 

 Service, Washington, D. C, 1913. 



Greene, Chas. T. : The Cambium Miner in River Birch. Journ. 

 Agr. Research, 1:6: 471-1, 1914. 



Nielsen, J. C. : Zoologische Studien tiber die Markflecke. Zool. 

 Jahrb., Abt. System, Geotigr. w. Biol. Trere, 23: 6: 725-738, 

 1906. 



Density and Weight (pp. 49-52) 



Dunlap, Frederick: Density of Wood Substance and Porosity of 

 Wood. Journ. Agr. Research, 2:6: 423-428, Sept. 1914. 



Gaskill, Alfred: Specific Gravity and Weight of the Most Im- 

 portant American Woods: A Study and Compilation. For. 

 Quarterly, 11: 4: 527-530, Dec. 1913. 



Record, Samuel J. : The Mechanical Properties of Wood. New 

 York, John Wiley & Sons, Inc., 1914, pp. 54-58. 



Permeability (pp. 60-62) 



Teesdale, Clyde H.: Relative Resistance of Various Conifers to 

 Injection with Creosote. Bui. 101, U. S. Dept. Agr., Wash- 

 ington, D. C, 1914. 



