Some Observations upon Spirostomum 

 ambiguuni (Ehrenberg). 



By 

 Ann Bishop, M.Sc, 



Victoria University, Manchester. 



With Plates 22 and 23 and 9 Text-figures. 



Contents. 



1. Historical ......... 



2. Material and Methods ...... 



Fixation ......... 



Staining ......... 



Observations on Living Specimens .... 



Feeding Methods 



3. Observations on the Morphology of Spirostomum ambiguum 



Contractile Vacuole ....... 



Endoplasm and Nuclei ...... 



The Micronuclei ....... 



Abnormalities in the form of the Meganucleus 



4. Methods of Cultivation ...... 



5. Food Cycle ........ 



6. Varieties of Spirostomum ambiguum .... 



7. Reproduction ........ 



A. Observations on the Growth and Reproduction of Spiro 



s t o m u m ambiguum during cultivation . 



B. Fission ........ 



C. Conjugation ....... 



8. Literature ..... ... 



9. Explanation of Plates 22 and 23 ... . 



D d 2 



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