Box.— Vol. I.] LAWSON—COBALA SCANDENS. 175 



perikaryoplasm from which it develops, but stains deeper 

 and deeper violet like the linin. At the points where the 

 threads intersect granules are seen. In fig. 8 the nuclear 

 wall is no longer continuous but is in the form of fragments. 

 To what extent the linin enters into the formation of the 

 network, the writer is at present unable to say, but it cer- 

 tainly appears to begin its formation. The amount of 

 linin present when the nuclear wall breaks down is not 

 sufficient to form the large central network that we see in 

 fig. 9. This network increases in size and apparently 

 grows at the expense of the perikaryoplasm. In fig. 9 

 the nuclear wall has entirely disappeared and the area once 

 occupied by the nucleus is now filled by a perfect network 

 which supports the chromosomes within its meshes. These 

 latter bodies appear to be more frequently present in those 

 places where the network is growing outward in the form 

 of projections. 



The contents of the cell is now beautifully differentiated 

 into three parts: the outer cytoplasmic reticulum which 

 stains light blue, the perikaryoplasm which stains orange, 

 and the central network which stains violet. Between 

 these latter two there is a transition place where the threads 

 of the central network become granular and stain less 

 deeply violet, until finally they become orange and pass 

 over into the granular substance of the perikaryoplasm, 

 where they can no longer be followed. 



In fig. 9 we see that the central network has at'cthree 

 places formed definite projections. How many of these 

 are generally formed it is difficult to make out from sec- 

 tions, but the number is nearly always more than two. In 

 fig. 10 we see that the meshes of the network have become 

 elongated in the directions in which the projections 

 extended. In fig. 12 we see that the meshes have a drawn- 

 out appearance, and we have the outline of a multipolar 

 spindle. Figure 11 is probably a later stage than fig. 12, 

 inasmuch as the meshes are drawn out to such an extent 

 as to present the appearance of distinct fibres, and we now 

 have the first spindle-fibres formed. In this figure it will 



