KOFOID AND SWEZY: UNARMORED DINOPLAGELLATA 



67 



forms is mainly clue to the investigations of Chatton, who pviblished his results 

 in a series of papers between 1906 and 1912. Pouchet (1885a) had earlier de- 

 scribed Oodhiium poucheti (= Gijnt nodi niton i)nlvisridiis) from Appendicu- 

 laria, and Bogiel (1906) added 0. parasiticum {=Gijnin(jdi>iium parasiticum) 

 from eopepod eggs and Chijtriodinium roseum {= Gymnodinium roseiim) from 

 coi^epod or other crustacean eggs. 



Fig. K. Developiiieut of Chytriodinium roseum (Dogiel). After Pogiel (lOOCi, pi. 2, figs. 26-35). 1. Small 

 amoeboid individual attached to crustacean egg. 2. Enlargement of parasite with third division of nucleus 

 in process. 3. Division of cytoplasm of parasite, contents of egg greatly diminished. 4. Further division of 

 C. roseum with egg greatly shrunken. 5. Completion of first sporoblast divisions. This stage corresponds to 

 that of figures 9, 4, 6. Kscaped sporoblast with contents dividing. 7. Further division of sporoblast. 8. 

 Gymnodi7iium-\ik.e individual escaped from cyst. X 500. 



The complete devclo])ment of these interesting organisms still awaits more 

 thorough investigation. The coutril)utions to their life history that have 

 already been made indicate a much higher degree of complexity than has been 



