340 CALIFORNIA ACADEMY OF SCIENCES. [Proc. 3D Ser. 



The shape of the daughter nuclei is decidedly ellipsoidal, 

 with the longest axis at right angles to the main axis of the 

 previous spindle. The daughter chromosomes are irregular 

 in shape: sometimes they take the form of lumps; at other 

 times they appear as chains of granules. They stain red 

 and are connected by bands of finely granular matter. A 

 body which seems to be a nucleolus appears in each 

 daughter nucleus. 



Owing to the presence of a dense granular zone around 

 each daughter nucleus, it was impossible to follow in this 

 case the stages just preceding the formation of the multi- 

 polar spindle; yet what could be seen was sufficient to 

 indicate that these stages agreed in the main with the cor- 

 responding stages of the mother nucleus. The differences 

 observed are to be explained by the shape of the spindle, 

 which in all cases is of a pronounced multipolar diarchal 

 type. 



The first indication of spindle formation that could be 

 observed was the appearance of a mass of clean-cut, 

 closely-woven fibers surrounding each daughter nucleus. 

 These fibers were particularly distinct where the nuclear 

 wall had shrunken somewhat. They stained a deep blue 



(fig- ^7). ^ ^ 



The multipolar spindles of the daughter nuclei are formed 

 in a manner similar to that of the mother nucleus. Linin 

 fibers become more and more prominent within the daugh- 

 ter nucleus; they run more or less parallel to the longest 

 axis of the nucleus in which they are formed. Cones begin 

 to appear here and there on the nuclear wall, usually at the 

 ends; they increase in number. In some places the nuclear 

 wall breaks down ; the cytoplasmic fibers enter the nuclear 

 cavity, and become merged with the threads of nuclear 

 origin. Finally a multipolar spindle is formed, which, as 

 has been previously stated, is of a pronounced multipolar 

 diarchal type. The narrow, compressed appearance of the 

 entire multipolar figure is here very striking, far more so 

 than in the multipolar spindle of the mother nucleus. In 

 no case was as large a number of poles observed as in the 



