640 
Wm. S. Marshall 
is best understood from a view of the figures. Iu figure 24 tliree 
epithelial cells are shown shortly after the formation of the chorion 
has beguu. It will be noticed that wherever there was, earlier, a con- 
striction in the nucleus, there now occurs a bend; these thin con- 
stricted parts are naturally the regions where the bending can easiest 
occnr. At this stage the cell boundaries can not be seen and in all 
the older stages it was impossible to find any. There does often occur 
a narrow open space at such positions as the cell boundaries would 
naturally occupy and in surface view the cells, low power, appeared 
clearly marked off from each other. 
With the greater flattening of the epithelial layer the nuelei 
becorne still more bent and twisted (Fig. 25). In this stage the sec- 
tions show many nuelei whicli have apparently divided, these, even 
in section as the figure just quoted will show, can most of them be 
seen to be one continuous piece. From the extreme thinness of some 
of the connecting Strands one is not always certain whetlier the pieces 
have really separated from each other or are still connected. A sur- 
tace view of a chamber of about the same age as this one figured 
shows the same thing (Fig. 27). The nuelei at this stage lie close 
together and nearly all show to some degree wliat is represented in 
the figure. 
In answer to the question ,.Does amitosis occur in the follicle 
epithelium of the ovary of the walking-stick?“, I would feel called 
upon to answer that examples miglit be found but that we do not 
have here what has been shown to occur in other insects. A glance 
at tliree or four of the last figures cited will show how difficult it 
is to always determine the presence of some of the Strands connec- 
ting different pieces of the nucleus especially where the parts overlap 
each other. There is no doubt that nuelei can be found in which 
two parts, perhaps unequal in size, have becorne disconnected from 
each other, but such examples are not common. We can see that a 
division of the nucleus is exceptional and is due, we think, to the 
excessive bending and twisting; the epithelial cells cannot in the old 
chambers be deseribed as binucleate as has been done for a number 
of other insects. 
Summary. 
The structure of the terminal filament and end chamber is very 
similar to what has been found in the Phasmidae, Sinety (24), Daiber 
(6). After the formation of the oöcyte chambers the epithelial cells 
