464 



SCIENCE 



[N. S. Vol. lAl. No. 1350 



Union of South Africa, has been appointed a 

 reader in estate management at Cambridge 



DISCUSSION AND CORRESPONDENCE 



THE PRESERVATION OF WILD LIFE 



The Ecological Society of America's com- 

 mittee on the preservation of natural condi- 

 tions, while unable to deal with problems con- 

 cerning wild life not in reserves, continually 

 encounters the fact that individual species 

 are menaced with extinction by agricultural 

 encroachments. Two of these menaces are: 

 1. Clean-culture (roadside mowing and 

 burning) as distinguished from roadside and 

 streamside shrubbery and bird and original 

 life preservation. 



Birds are decreasing for lack of nesting 

 sites, on account of destruction of breeding 

 conditions. Entomologists and some agricul- 

 turists maintain that this condition is nec- 

 essary to agriculture. Bird men insist that 

 birds are also essential. It is known that a 

 few states encourage roadside shrubbery while 

 several require roadside mowing. The prac- 

 tise in the various parts of the United States 

 and Canada should be ascertained. The effect 

 of different procedures should be determined. 

 The areas in which specially destructive and 

 drastic measures such as burning for insect 

 pests are necessary should be clearly defined 

 and limited and the public informed as to 

 the dangers of such burning. 



2. Upland marshes are important as sponges 

 storing water and letting it out slowly during 

 dry seasons, thus controlling floods. Such 

 marshes are gradually being drained and the 

 flood menace is increasing every year. 



The only way to save these natural re- 

 sources and at the same time, the swamp 

 faunas, especially the birds, is to utilize the 

 swamps for aquiculture. To this end several 

 water-culture experiment stations should be 

 established. For the present there should be 

 one, perhaps at Cornell University, to deal 

 with the upland marsh problems. There should 

 be another in connection with Okefinokee 

 swamp and one in connection with the coastal 

 swamps of New Jersey. In addition to frogs. 



fish, and birds, a nimiber of plants are good 

 for food, etc.; e. g., cattail flour and cattail 

 paper have recently been tried with success. 

 Swamp potatoes, the corns of arrowhead, and 

 seeds, roots, and stalks of our native lotus 

 served as food for the American aborigines 

 and pioneers. Hedrick (Science, 40:611), 

 Claussen {Sci. Mo., 9 :179), and Needham and 

 Lloyd (" Life of Inland Waters ") have dis- 

 cussed these questions and suggested or ad- 

 vocated the improvement and culture of 

 aquatic plants. 



It is the belief of the committee that all 

 organizations in any way interested should 

 combine efforts for the investigation of these 

 questions. 



Eor a list of the committee members, see 

 Science, March 26, 1920; since that date the 

 following have been added: Z. P. Metcalf, 

 University of North Carolina; C. A. Shull, 

 University of Kentucky; E. M. Harper, Col- 

 lege Point, N. Y. ; and Jens Jensen, Eavinia, 



^^i'lo^^- V. E. Shelford, 



Chairman 



University of Illinois 



predilection and sampling of human 



HEIGHTS 



To THE Editor of Science: Extensive reli- 

 able data showing the distribution of human 

 heights in " unselected " populations are sur- 

 prisingly hard to obtain. The Association of 

 Life Insurance Medical Directors and the Ac- 

 tuarial Society of America have, however, 

 undertaken a very careful statistical study of 

 men accepted for life insurance,^ which pro- 

 vides, among other things, a distribution of the 

 heights of 221,819 men. Here, at last, we 

 might expect to settle the question of the form 

 of distribution that would hold for a popula- 

 tion, but we discover in the distribution curve 

 a remarkable inversion that it is difficult to 

 explain as anything other than an artefact. 



This distribution curve is the solid line of 

 the figure. The average height is 5 ft. 8.49 in. 

 Since the curve is plotted in units of an inch, 



1 ' ' Medico-Aetuarial Mortality Investigation, ' ' 

 Vol. I., 1912, esp. 11-22. 



