ne Ohio i\Ccituralist, 



PUBLISHED BY 



The Biological Club of the Ohio State Uni'versity, 



Volume VIII. MAY. 1908. No. 7. 



TABLE OF CONTENTS. 



Dachnowski— Type and Variability in the Wood-increment of Acer Rubrum L 343 



Hubbard— Stream Diversion near Lalu'ville. Ohio 349 



DORRANT— Description of New Mallophaga. Ill 355 



Carney and Brumback— The Deposits of Glass Sand at Toboso, 358 



On the Death of William Ashbrook Kellcrman 3G1 



TYPE AND VARIABILITY IN THE ANNUAL WOOD- 

 INCREMENT OF ACER RUBRUM L. 



Alfred Dachnowski. 



In all temperate zones, at least, trees form annually one 

 layer of wood, which appears on a cross-section of a tree as a 

 ring, more or less clearly defined. The rate at which the dia- 

 meter and the area of any cross-section of the tree increases, can 

 therefore be easily ascertained by measuring the width of the 

 rings. To obtain direct evidence as to the relation of the rate 

 of wood formation to the nature of the habitat, and to obtain 

 information on the value of a biometric study in diflierentiating 

 such habitats, statistical work has been carried out during the 

 past winter of 1907-8. The work was done in connection with 

 an inquiry on the toxic properties of bogwater and bogsoils, 

 the data of which, correlated with this and other studies, will 

 be brought out elsewhere in another paper. 



The purpose of the article here briefed is to call attention to 

 the fact that statistical methods first used by Galton and now 

 applied by Pearson (7), Davenport (4), Shull (8), and others to 

 the more complicated questions in variation and heredity, may 

 be of service also in Forestry problems as well as in questions 

 of Ecology. 



About 25 miles east of Columbus occurs an extensive lake, 

 approximately ten miles long and one mile wide, known as Buck- 

 eye Lake. Near the northern bank, and midway between the 

 small towns of Lakeside and Avondale is a bog-island very near- 

 ly one-tenth the dimensions of the lake. Soundings made to 

 determine the character of the peat gave 30 to 40 feet as the 

 depth of the island. Its vegetation presents two well-marked 

 zones, — a central one consisting of Sphagnum, Carex, Erio- 

 phorum, Oxycoccus, Drosera, Rhus vernix, Aronia nigra, 

 and others, and a marginal zone which includes besides several 

 species of SaUx, Akius incana, A. rugosa, Ilex verticillata, Comus 



