246 
J. 0. Wakelin Barratt and G. Arnold 
In their first communication Bergonie and Tribondeau made use 
of an intensity of X radiation represented by four Holzknecht nnits, the 
distance of the animal from the anticathode being 15 cm. A series of 
exposures of 2 to 10 minutes duration was given at intervals of 1 to 8 days. 
Macroscopicallv most of the testes were unaltered in their aspect; some 
appear to have been softened and to have become more translucent in 
appearance. 
In their second paper Bergonie and Tribondeau describe the mi- 
croscopical changes occurring in the testes of the rats experimented upon. 
Examined immediately after the conclusion of the- exposure to X rays, 
commencing disintegration of the seminiferous epithehum was met with, 
and as this had advanced unequally in different tubules it was easy 
to recognize the various stages of its progress. Karyokinetic figures 
had everywhere disappeared. Large spermatocytes were rare; where 
they persisted their chromatin filament became fragmented into micro- 
cliromosomes, which were at first arranged in a stippled spireme, tlien 
became scattered, lost their colour and finallv disappeared (karyorrhexis). 
The large spermatocytes rarely became destroyed by pycnosis. The 
small spermatocytes, spermatogonia, and spermatids persisted longer, 
their nuclei undergoing pycnosis. In the spermatocytes and spermato- 
gonia chromatic concentration occurred, which in the spermatids 
was at fii;st annular. The pycnotic nuclei became fragmented and 
tlien underwent liquefaction. In the different cells, chromatoid masses, 
intra- and extra-nuclear were frequently observed. The spermatozoa 
disappeared more slowly, but finally adhered together and became 
dissolved. The cells of Sertoli persisted and their nuclei, which 
remained intact and were easily identified, underwent amitotic divis- 
ion and invaded the lumen of the seminiferous tubule. In tubules 
which had been severely affected, in which advanced destruction had 
ocurred, the cells of Sertoli were themselves altered, staining dif- 
fusely, then finally fading and disappearing. When the testes were 
examined a month and a half after the conclusion of the exposure to 
X rays the degeneration had become complete. All trace of dead 
cells had disappeared, and already signs of regeneration could be 
recognized, viz: abundant amitotic division of the cells of Sertoli in 
the aspermatogenous tubules, karyokinesis in the spermatogenous 
tubules. From this description it follows that the action of X rays is not 
to cause a simple desquamation of the seminal epitlielium followed by 
its expulsion, but to produce Chemical and structural alteration followed 
by resorption in situ. The nutritive syncytium remains for a long time 
