Katharine Foot and E. C. Strobell 21? 



the germinal vesicle takes part in forming the chromosomes of the 

 first spindle. The evidence points rather to the conclusion that the 

 apparent surplus of chromatin in this egg is due to its earlier artificial 

 combination -with the achromatic substance causing a misconception as 

 to the actual amount, and that all the chromatin, excepting that possibly 

 contributed to the accessory nucleoli, is finally consigned to the chromo- 

 somes. 



We have not attempted to analyze the reticulum by differential anilin 

 staining, because the experimenting we have done Math anilins on later 

 stages of the egg, has convinced us of the justice of the criticism of those 

 investigators who question all results obtained by this method. Our aim 

 is to ])lace in evidence only such phenomena as can be seen and photo- 

 graphed without the aid of any complicated method of staining, and in 

 nearly all cases we control the evidence of the stained preparations by 

 photographs of unstained sections, e. g.. Photos. 68 and 69, Plate IV, 

 and forty other unstained sections showing nucleoli, centrosomes, archo- 

 plasm, etc. 



With thin unstained sections much can be seen and photographed at a 

 thousand diameters — tlie centriole and even individual microsomes can 

 he clearlv registered hy photographs and such evidence as this method 

 furnishes is at least relatively reliable. It may be an objection that this 

 simple method throws out of court a number of so-called nuclear struc- 

 tures, for we are indelited to the anilin stains for several analytical sub- 

 divisions of the reticulum, e. g., Heidenhains' lanthanin or oxy chro- 

 matin granules which, according to Tellyesniczky. '02, are the same as 

 Schwartz's paralinin and Pflitzner's parachromatin — the non-staining 

 linin, and Eeinke's oedematin spheres, or cyanophilous granules. It may 

 be justly asked, whether this is a question of indebtedness to the anilins 

 or a score to settle. 



Chromosomes. — The development of the 11 tetrads and their subse- 

 quent division in the first maturation spindle are so clearly demonstrated 

 hy our new method descril:ied on p. 200 that the successive steps of the 

 process can be illustrated l)y a few photographs " of these preparations 

 (Plates YII, YIII and ix"). 



In the dried germinal vesicles of eggs from the distal end of the ovary 

 and of the youngest eggs from the receptacida ovorum we have been 

 unable to identify any differentiation of the nucleoplasm into the rela- 



"We have more than two hundred preparations demonstrating these stages 

 with equal clearness and many of these we have already photographed. In 

 a future paper we shall reproduce some of them in connection with photo- 

 graphs of later stages demonstrated by the same method. 



