276 J. 0. Wakelin Barratt and G. Arnold, Cell Changes in tlie Testis etc. 
Fig. 29. Degenerated spermatid lying close to tlie lumen of a seininiferous tubule. 
The spermatozoal liead is formed. but is degenerated and curled up in the cytoplasm 
wliicli is filled witli numerous fatty masses. 
Fig. 30. Seminiferous tubule thirtheen days after the application of X rays. 
All the seminal cells have disappeared. Extemally the basement membrane is seen. 
Distributed within the tubule are numerous nuclei of cells of Sertoli the cytoplasm 
of which forms a coarse framework, within the meshes of which fatty masses, more 
or less darklv stained witli osmic acid, are sparselv scattered. Xo definite lumen is 
present in the tubule. 
Fig. 31. Seminiferous tubule eleven days after the application of X rays. Tlie 
seminal cells have disappeared, tlieir place being taken by numerous fatty masses 
stained in varying degrees of darkness by osmic acid. The nuclei seen are those of 
cells of Sertoli, the cytoplasm of which forms a loose meshwork tliroughout the tubule. 
The lumen of the tubule has become obliterated. 
Fig. 32. Portion of a healthy seminiferous tubule for comparison witli the two 
preceding Figures. To the left the basement membrane is seen. To the right of this 
lie ths seminal cells, among which are recognizable spermatogonia (in contact witli 
the basement membrane) cells of Sertoli, spermatocytes of the first Order, spermatids 
and spennatozoa, the tails of the latter being free in the lumen of the tubule. Near 
the basement membrane large fatty masses are seen; towards the lumen of the tubule 
collections of small fatty globales lying within the cytoplasm of the spermatids are 
shown. 
