194 MC/NSO.V. [Vol. XV. 



chromatin granules or else some substance capable of fixing 

 the Lyon's blue more strongly than the carmine. The latter 

 substance is not to be observed in the germinal vesicle, for 

 no part of it takes the blue stain when carmine or safranin is 

 associated with the Lyon's blue. 



From these considerations, and others that will appear in 

 another connection, it may be said that ike vitelline-body docs 

 not arise in the cytoplasm of the growing egg ; neither docs it 

 arise as a bud of the germinal vesicle ; nor as extruded chrotna- 

 tin, nor as migrating nucleoli. It contains no nuclear chromatin. 



In this connection, a few further considerations concerning 

 Lyon's blue as a stain may be added. This stain not only dif- 

 ferentiates the body under consideration in its earliest stages ; 

 but, in material preserved in suitable hardening reagents, it 

 differentiates it conspicuously as long as safranin or carmine 

 can be associated with it. This, however, ceases when the 

 first period of growth is passed, since, after that period, these 

 stains do not affect the granules of the cytoplasm. Yet, even 

 after this, the body is made conspicuous by means of Lyon's 

 blue used alone, because of its greater affinity for the stain and 

 consequently deeper blue coloration. It may thus profitably be 

 employed even in larger eggs of the second and third stages. 



Even in those cases where nothing corresponding to the 

 archoplasm appears, where the fibers of the cytoreticulum con- 

 verge to a point as previously described, thus forming either a 

 real, conspicuous aster, or a more irregular area with radial 

 fibers, the center of this system is made conspicuous by the 

 Lyon's blue, all the other parts of the egg being stained red 

 by means of safranin. Where the body assumes the form of 

 a large compact sphere of interwoven or concentric fibers, also, 

 it is made prominent as a blue or green sphere standing out 

 conspicuously from all the rest of the egg. 



Although this stain, therefore, has a decided affinity for this 

 body, I cannot regard it as a specific stain, for it shows also a 

 decided affinity for the egg membrane after it has acquired 

 several layers. Its general nature as a stain is evident further 

 in those eggs belonging to the third stage, where it has been 



po 



intcd out that numerous nuclei are found within the egg. 



OO" 



