VI CONTENTS 



FaK* 



Our petroleum supply, by Hugh D. Miser 303 



Biologic balance on the farm, by W. L. McAtee 319 



On the frontier of British Guiana and Brazil, by Capt. H. Carington 



Smith, R. E 325 



The sea bird as an individual: results of ringing experiments, by R. M. 



Lockley 341 



Birds and the wind, by Neil T. McMillan 355 



Bookworms, by E. A. Back 365 



The problem of conserving rare native plants, by M. L. Fernald, D. C. L., 



D. Sc 375 



Plankton in the water supply, by Florence E. Meier 393 



Trichinosis in swine and its relationship to public health, by Benjamin 



Schwartz 413 



Closing the gap at Tepe Gawra, by E. A. Speiser 437 



Sun worship, by Herbert J. Spinden 447 



The use of soapstone by the Indians of the eastern United States, by 



David I. BushneU, Jr 471 



The modern growth of the totem pole on the northwest coast, by Marius 



Barbeau 49 1 



Historic American highways, by Albert C. Rose 499 



Modern trends in air trausport, by W. F. Durand 513 



The story of the Time Capsule, by G. Edward Pendray 533 



