GENUS: SPIROMONAS 



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brought about by the flagellate losing its flagella and becoming spherical. 

 Within the cyst it divides usually into three, but sometimes into two or 

 four small forms, which develop flagella and escape from the cyst, Syn- 



FiG. 143. — Spiromonas angnsta : A Coprozoic Flagellatk from Pig's F.eces 

 ( X 3,000). (Original.) 



1-2. Narrow fornis showing spiral groove. 

 3-4. Thicker fornis in which spiral groove is not evident. 



5-6. Forms witiuiut tiagella retracting for encystment; one has a large vacuole. 

 7-8. Encysted forms with one nucleus; one has a vacuole. 

 9-10. Similar forms with two nuclei. 11. Encysted form with four nuclei. 



12. Encysted form after division into four; each develops two flagella and escapes from 

 the cy.st. 13-14. Encysted forms after division in two. 



gamy was also observed to take place. Two individuals may form a 

 common cyst, within which they unite, or they may first unite and form a 

 cyst afterwards. A coprozoic Sjnromonas has been seen by the writer in 



