Mar. i, i92! Effects of X-Rays on Trichina 849 



that regularly occurs soon after the parasites reach the intestines, they 

 underwent degenerative changes, and even in those cases in which the 

 parasites developed to sexual maturity the reproductive processes 

 were seriously disturbed. That the reproductive organs are especially 

 susceptible to X-ray injury is clearly shown by the results of experiment 

 2. In this experiment the larvae succeeded in attaining maturity, but 

 the sex cells evidently failed to function. 



It is also interesting to note that despite the fact that several rats 

 in experiment 3 were not fed until 6 days after the meat had been exposed 

 to X-rays, the animals developed an infection. Thus, in this experiment 

 there was evident neither an immediate nor a delayed effect of the X-ray 

 treatment upon the encysted parasites. 



SERIES 11 



Three experiments are included in this series. The units of dosage 

 used in this series have the same relative values as those in series I. 

 Under date of February 5, 19 17, the roentgenologist writes as follows: 



The package marked "A" (experiment 7) was given 600 units, the package marked 

 " B " (experiment 8) 300 units, and the package marked " C" (experiment 9) 350 units. 

 The 300 units given to package " B " were given with low density and extra long time. 

 The packages marked "A" and " C" were given the 600 and 3 50 units, respectively, at 

 high tension — that is, close to the tube and with short time. 



Experiment 7. — Strength of dosage, 600 units. The meat was 

 exposed 19 minutes. 



Three rats were fed on February 8. Rat 1 died on March 1 ; diaphragm 

 negative. Rat 2 died on March 2; diaphragm showed a slight infesta- 

 tion with trichinae. Rat 3 died on March 6; diaphragm slightly infested 

 with trichinse. 



Experiment 8. — Strength of dosage, 300 units. The meat was 

 exposed 46 minutes. 



Three rats were fed on February 8. Rats 1 and 2 died February 12; 

 live trichinae were found in the intestines. Rat 3 died on February 26; 

 numerous larvae were found in the fluid expressed from the diaphragm. 



Experiment 9. — Strength of dosage, 350 units. The meat was 

 exposed 10^2 minutes. 



Four rats were fed on February 8. Rat 1 died on February 21; 

 numerous live trichinae in intestines. Rat 2 died on February 28; 

 diaphragm infested with encysted trichinae. Rat 3 died on March 1; 

 results as in No. 2. Rat 4 died on March 2 ; diaphragm heavily infested 

 with trichinae. 



Results of experiments of series II. — The parasites in the meat 

 used in experiment 7 were evidently affected by the exposure. That 

 some of them, however, escaped the injurious influences of the exposure 

 to X-rays may be concluded from the results of the feeding experiments 

 which resulted in rather slight infections. 



