THE SPERMATOGENESIS OF THE MYRIAPODS. 



195 



geneous mass of chromatin. Since then, however, I have studied 

 this structure under more favorable circumstances, and am able to 

 demonstrate that this is not true. In my earlier studies sections 

 six and two thirds micra thick were used and these were studied 

 under a magnification of one thousand diameters. In arriving 

 at my later results thin sections two to three micra thick were 

 used as well as the thicker ones. These were stained in varying 

 intensities with HeidenhaifVs iron-haematoxylin and were studied 

 at a magnification of twelve hundred to eighteen hundred diame- 

 ters. With these improved conditions it is found that this body, 

 which I shall hereafter call the karyosphere, is by no means a 

 simple homogeneous sphere of chromatin, but on the contrary is 

 a rather complex structure consisting of chromatin, linin and 



FIG 9. X I 544 dia. Karyosphere as seen in various preparations; a, as it ap- 

 pears in thick densely stained sections ; b, karyosphere in which the chromatin seg- 

 ments are massed together by the action of the fixing reagents ; c, thin lightly stained 

 section of karyosphere showing the real normal structure ; d, section through one side 

 of karyosphere ; e , karyosphere in early prophase shortly before the appearance of the 

 chromosomes. 



Fir,. 10. X I >44 dia. Nucleus of first spermatocyte in prophase, showing the 

 origin of the chromosomes from the karyosphere. A number of segments have al- 

 ready become detached and lie free in the nucleus while others are still connected 

 with the karyosphere. Those detached have already segmented longitudinally. 



karyolymph. It is a mass of fine granular filaments of chromatin 

 so closely gathered about the accessory chromosome as to pre- 

 sent, under ordinary conditions and amplification, the appearance 

 of an irregular homogeneous sphere of pure chromatin (Fig. 9, a). 



