Cell Changes in the Testis due to X Rays. 
271 
division. The inquiry presents itself, is division by amitosis in sper- 
matocvtes of the second order, after the application of X rays, com- 
parable in part to the process of mitosis. The points of resemblance 
betweenthe two are; Separation of the chromatin into two approximately 
equal portions (direct in amitosis, indirect in mitosis); division of the 
hyaloplasm of the nucleus; Separation of cytoplasm. The points of 
difference lie in the omission of the following processes in amitosis: 
Separation of the centrosomes; the formation of a spindle; differen- 
tiation of the nucleus into spireme and subsequently into chromosomes. 
Turning now to disturbance of cell development, an excellent Illu- 
stration is afforded by the marked enlargement of the archoplasmic vesicle 
leading to the formation of a large vacuole (Fig. 28), which occurs as an 
exaggeration of one of the many complicated and obscure processes by 
means of which the spermatid is transformed into a Spermatozoon. In 
many cases this change appears to occur alone, the cell not presenting 
any other marked alteration except compression of the nuclear substance ; 
in other cases, however, it becomes obvious that additional disturbances 
of function are in action, e. g. incomplete Separation (or possibly fusion) 
of the individual spermatids, resulting in the formation of cell masses 
(Fig. 24), or the appearance of smaller vesicles (Fig. 28). 
Finally as a type of disturbance of an apparently purely nutritive 
character following upon the application of X rays, may be taken the 
formation of large vacuoles round the intranuclear body (Fig. 14) and •> 
also of intranuclear vacuoles similar in appearance to these except that 
they do not contain any intranuclear body. It is possible that the latter 
vacuoles may be derived from the former by the disappearance of the 
intranuclear body. We have not however been able to trace any inter- 
mediate steps of such disturbances. 
Description of the illustrations. 
Plates XXIII-XXIV. 
The Illustrations refer to the testis of the rat. Figs. 1 to 12 and 32 represent 
normal appearances ; the remaining Figures are made from festes which had been ex- 
posed one to twelve days previously to the action of X rays. 
As hardening fluid Flemming’s solution (strong) was employed. For staining 
Heidenhain’s iron alum haematoxylin method was used with Orange G as a counterstain. 
Figs. 1 to 29 are magnified 2,700 diameters, (comp. oc. 18; apo. obj.2mm) the 
scale being shown below Fig. 12; Figs. 30 to 32 are magnified 460 diameters (oc. 3; 
obj. 4 mm) the scale being given below Fig. 30. chr.b = chromatoid body; a = archo- 
plasm; i.s. = intermediate substance; i.b. = intranuclear body; m = manchette. 
