94 WM - S. MARSHALL. 



Explanation of Plate V. 

 All figures drawn with a camera-lucida. 



Fig. i. Small piece of a Malpighian tubule from an embryo walking-stick. 

 X 2,200. 



Fig. 2. A nucleus showing early stage of amitotic division ; from a large tubule. 

 X75°- 



Figs. 3 and 4. Nuclei in a somewhat later stage ; both from small tubules. 

 X 1,200. 



Fig. 5 . Elongation of nucleus preparatory to division ; from large tubule. 

 X 1,200. 



Fig. 6. Nucleus of large tubule after completed division. X I > 2 °°- 





