ABNORMAL DEVELOPMENT OF TOAD OVA FER- 

 TILIZED BY SPERMATOZOA EXPOSED TO THE 

 ROENTGEN RAYS 



BY 



CHARLES RUSSELL BARDEEN, M.D. 



Professor of Anatomy, University of Wisconsin, Madison, Wis. 



With Five Plates 

 REVIEW OF THE LITERATURE 



The marked alterations in structure and function produced in 

 living tissues by the Roentgen rays and the rays of radium have 

 excited much interest in the medical profession. Professional 

 biologists have paid less attention to the subject, although it is one 

 which promises to be of great importance to those engaged m 

 experimental morphology. While probably all living tissues may 

 be injured by sufficient exposure to these rays, there are great 

 differences in the degree of susceptibility of different tissues and 

 organisms. The power of assimilation of foodstuffs and their 

 transformation into living structures complex in character seems 

 to be that which is most altered in exposed tissues. 



Bacteria are less easily affected than are most of the higher organ- 

 isms. Many of those who have exposed cultures of bacteria to 

 the Roentgen rays have failed to discover any checking of the nor- 

 mal multiplication of the bacteria.^ Rieder,^ on the other hand, 

 found growth of bacteria inhibited by sufficient exposure to the 

 rays. Those who have studied the action of radium on bacterial 

 cultures have usually found the growth of the bacteria inhibited 



^Park, Medical News, 1896; Mink, Munchener med. Wochenschrift, 1896; Lyon, Lancet, 1896; 

 Delepine, British Medical Journal, 1896; Atkinson, Nature, Ivi, p. 600, 1897 (negative results with 

 mucor, bacteria and oscillaria). 



^Rieder: Munchener vr d. Wochenschrift, 1902. 



The Journal of i>erimental Zoology, vol. iv, no. i. 



V 



