196 
Katharine Foot and E. C. Strobell 
do not agree in their Interpretation of these facts. We believe that a 
comparison of their observations on these two fornis with certain facts 
that can be demonstrated in Protenor may throw some light on obscure 
points and aid in their interpretation. 
Without attempting for a moment to pass judgment on tlie opposing 
interpretations of these two investigators, we believe that the evidence 
in Protenor is in accord with Will’s interpretation of some of the facts, 
and this evidence in Protenor can be clearly demonstrated by a series 
of photographs. The observations of Will and Korschelt agree as 
to the following facts. In the anterior area (zone A) of the terminal 
chamber of both Notonecta and Nepa there are small nuclei imbedded 
in a common protoplasmic mass, cell boundaries being rarely seen. These 
nuclei increase greatly in size and finally occupy a definite Posit- 
ion in the terminal chamber (Zone B. figs. 1 and 2 and pliotos 1 and 2). 
Suddenly at the base of the terminal chamber we again find an accu- 
mulation of small nuclei (zone C, figs. 1 and 2 and photos 1 and 2). Both 
investigators agree as to these facts and they further agree that at this 
point the large nuclei, as such, disappear, they break up into small frag- 
ments. Both investigators find in this area (zone C) many small nuclei, 
but they disagree as to their origin. Will claiming they owe their origin 
to the large nuclei. whereas Korschelt believes they are a continuation 
of small nuclei which are in the anterior area of the terminal chamber 
(zone A) and liave no connection with the products of disintegration of 
the large nuclei. 
Korschelt interprets the large nuclei of zone B as purely nourishing 
cells (“Kahrzellen”) which in the lower zone (zone C) degenerate, dis- 
integrate and disappear. Will, on the contrarv, interprets these large 
nuclei (zone B) as oöblasts and Claims that they give rise to many small 
nuclei which become differentiated into epithelial cells and egg cells. 
Whether the large nuclei fragment or whether their nuclear contents 
simply flow out, or again, whether the process differs for the epithelial 
nuclei and for the germinal vesicles are details which have no essential 
bearing on the main fact we shall aim to demonstrate — namelv, that 
the disintegration of the large nuclei gives rise to many smaller nuclei — 
these nuclei representing the accumulation of small nuclei that both 
Will and Korschelt have demonstrated in zone C, and which they 
both interpret as giving rise to epithelial and egg cells. The important 
point of divergence between these two investigators is the question whether 
the disintegration products of the large nuclei of zone B are purely 
“nourishing material”, according to Korschelt, or whether they also 
