T^S8 MONTGOMERY. [Vol. XV. 



Kernfadeu, kyanophil"; these disappear before the mitosis, 

 while the Eunucleoli remain until about the end of the spirem 

 stage. Vacuoles arise only in the Eunucleoli. 



Rosen in a second paper ('92b) presents further observations 

 upon nucleoli. Myxomycctes : the spore nucleus contains one 

 large nucleolus. Fuligo septa, plasmodium : one large, cyano- 

 philic nucleolus, which he terms " Mittelkorperchen," since in 

 the atypical mitosis this body lies in the middle of the pole 

 plate, and disappears at the end of the nuclear division. Syn- 

 chrytrium : one large nucleolus with several vacuoles ; in the 

 first mitosis the division of this nucleolus precedes that of 

 the nucleus, but during subsequent divisions the nucleoli 

 vanish. In Cystopits there is no nucleolus. 



Schottlander ('92), cells of cryptogams : the nucleus consists of 

 a blue-staining substance (network), and a red-staining (nuclear 

 membrane, nucleoli). Egg cell of Gy7}inogrammc cJirysopJiylla : 

 here are one or several large nucleoli, each surrounded by a 

 vacuole ; in the ripe egg the nucleoli are filled with small glob- 

 ules. Egg cell of CJiara : the nucleoli contain vacuoles, which 

 later become so large in the largest nucleoli that they become 

 polygonally flattened against one another, and their thin walls 

 then present the appearance of a network within the nucleolus. 

 Demoor ('93), mitosis of Tradescantia : the nucleoli gradually 

 disappear during the prophase. 



Gjurasin ('93) investigated the nuclear division of Peziza. 

 In the nucleus is one large, excentric nucleolus, which stains 

 red with Flemming's triple stain, while in it as many as six 

 granules may occur, and these stain violet. In the mitosis 

 these granules disappear, but otherwise the nucleolus does not 

 change at first, but occupies its original position within the cell, 

 though now in the cytoplasm; eventually it disappears gradually. 

 In each daughter-nucleus a new nucleolus arises, which appar- 

 ently has no genetic connection with the mother-nucleolus (now 

 vanished). " Ich bin der Ansicht, dass . . . das Kernkorper- 

 chen nicht eine Art von Reservestoff darstellt, sondern ein 

 specifisches Organ des Zellkernes ist." 



Karsten ('93), nuclear division of Psilotmn : in the resting 

 nucleus are two or three nucleoli, which are homogeneous, oval 



