FURTHER NOTES ON THE EGG OF ALLOLO- 

 BOPHORA FOETIDA. 



KATHARINE FOOT AND ELLA CHURCH STROBELL. 



Preface. 



In the autumn of 1894, while I was studying living eggs 

 from the ovaries of AllolobophoTa foctida with a Zeiss 2 mm. 

 immer. lens., Dr. Whitman sugcrested that I kill the o.zz's, 

 under this high magnification in order to observe the effect of 

 the fixatives. I made many attempts, but was unable to over- 

 come the technical difficulties sufficiently to make the method 

 of any value. The following spring I experimented with eggs 

 from the cocoons ; but found it impossible, without injury 

 to the egg, to hold it steadily in the field while applying the 

 fixative. This summer, by the aid of the Bausch and Lomb 

 compressor, Miss Strobell and I have been able to get more 

 satisfactory results, for it has been possible with this compressor 

 to hold the eggs firmly and yet so gently that they continue to 

 develop normally, forming the polar bodies, etc. 



Ziegler's (10) classic work on the living Nematode eggs led 

 me in the spring of 1896 to commence the study of the living 

 (cocoon) eggs of AllolobopJiora foctida, and at that time I 

 began a comparative study of the living and fixed cytoplasm of 

 these eggs. It was my aim to be able to place side by side 

 illustrations of the living cytoplasm with illustrations of the 

 same stages killed by different fixatives, hoping by that method 

 to support or correct my earlier interpretations.^ 



Since the spring of 1897 Miss Strobell has been associated 

 with me in this work ; and, as our results have been attained 



1 I quote the following from a paper sent to press Deceml)er, 1897, and which 

 will appear in Journ. of Morph., voL xiv, No. 3, 1898. "As I am at work on a 

 paper which will give the results of a comparative study of the living and fixed 

 cytoplasm in these eggs, I shall omit here any description of the living normal 

 cytoplasm." 



